diff --git a/bybit_api_client.go b/bybit_api_client.go
index d9b807d..8cbc2ee 100644
--- a/bybit_api_client.go
+++ b/bybit_api_client.go
@@ -5,23 +5,33 @@ import (
 	"context"
 	"crypto/hmac"
 	"crypto/sha256"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
-	handlers "github.com/wuhewuhe/bybit.go.api/handlers"
+	"github.com/wuhewuhe/bybit.go.api/handlers"
 	"io"
 	"log"
 	"net/http"
 	"os"
+	"strconv"
 	"time"
 )
 
+type ServerResponse struct {
+	RetCode    int         `json:"retCode"`
+	RetMsg     string      `json:"retMsg"`
+	Result     interface{} `json:"result"`
+	RetExtInfo struct{}    `json:"retExtInfo"`
+	Time       int64       `json:"time"`
+}
+
 // TimeInForceType define time in force type of order
 type TimeInForceType string
 
 // Client define API client
 type Client struct {
 	APIKey     string
-	SecretKey  string
+	APISecret  string
 	BaseURL    string
 	HTTPClient *http.Client
 	Debug      bool
@@ -39,29 +49,13 @@ func WithDebug(debug bool) ClientOption {
 	}
 }
 
+// WithBaseURL is a client option to set the base URL of the Bybit HTTP client.
 func WithBaseURL(baseURL string) ClientOption {
 	return func(c *Client) {
 		c.BaseURL = baseURL
 	}
 }
 
-func currentTimestamp() int64 {
-	return FormatTimestamp(time.Now())
-}
-
-// FormatTimestamp formats a time into Unix timestamp in milliseconds, as requested by Bybit.
-func FormatTimestamp(t time.Time) int64 {
-	return t.UnixNano() / int64(time.Millisecond)
-}
-
-type ServerResponse struct {
-	RetCode    int         `json:"retCode"`
-	RetMsg     string      `json:"retMsg"`
-	Result     interface{} `json:"result"`
-	RetExtInfo struct{}    `json:"retExtInfo"`
-	Time       int64       `json:"time"`
-}
-
 func PrettyPrint(i interface{}) string {
 	s, _ := json.MarshalIndent(i, "", "\t")
 	return string(s)
@@ -74,11 +68,11 @@ func (c *Client) debug(format string, v ...interface{}) {
 }
 
 // NewBybitHttpClient NewClient Create client function for initialising new Bybit client
-func NewBybitHttpClient(apiKey string, secretKey string, options ...ClientOption) *Client {
+func NewBybitHttpClient(apiKey string, APISecret string, options ...ClientOption) *Client {
 	c := &Client{
 		APIKey:     apiKey,
-		SecretKey:  secretKey,
-		BaseURL:    "https://api.bybit.com",
+		APISecret:  APISecret,
+		BaseURL:    MAINNET,
 		HTTPClient: http.DefaultClient,
 		Logger:     log.New(os.Stderr, Name, log.LstdFlags),
 	}
@@ -104,49 +98,47 @@ func (c *Client) parseRequest(r *request, opts ...RequestOption) (err error) {
 	fullURL := fmt.Sprintf("%s%s", c.BaseURL, r.endpoint)
 
 	queryString := r.query.Encode()
-	body := &bytes.Buffer{}
-	bodyString := r.form.Encode()
 	header := http.Header{}
+	body := &bytes.Buffer{}
+	if r.params != nil {
+		body = bytes.NewBuffer(r.params)
+	}
 	if r.header != nil {
 		header = r.header.Clone()
 	}
 	header.Set("User-Agent", fmt.Sprintf("%s/%s", Name, Version))
-	if bodyString != "" {
-		header.Set("Content-Type", "application/json")
-		body = bytes.NewBufferString(bodyString)
-	}
+
 	if r.secType == secTypeSigned {
+		now := time.Now()
+		unixNano := now.UnixNano()
+		timeStamp := unixNano / 1000000
 		header.Set(signTypeKey, "2")
 		header.Set(apiRequestKey, c.APIKey)
-		header.Set(timestampKey, fmt.Sprintf("%d", currentTimestamp()))
+		header.Set(timestampKey, strconv.FormatInt(timeStamp, 10))
 		if r.recvWindow == "" {
-			header.Set(recvWindowKey, "5000")
+			r.recvWindow = "5000"
+		}
+		header.Set(recvWindowKey, r.recvWindow)
+
+		var signatureBase []byte
+		if r.method == "POST" {
+			header.Set("Content-Type", "application/json")
+			signatureBase = []byte(strconv.FormatInt(timeStamp, 10) + c.APIKey + r.recvWindow + string(r.params[:]))
 		} else {
-			header.Set(recvWindowKey, r.recvWindow)
+			signatureBase = []byte(strconv.FormatInt(timeStamp, 10) + c.APIKey + r.recvWindow + queryString)
 		}
-
-		var signatureBase string
-		if r.method == "GET" {
-			signatureBase = fmt.Sprintf("%d%s%s%s", FormatTimestamp(time.Now()), c.APIKey, r.recvWindow, queryString)
-		} else if r.method == "POST" {
-			signatureBase = fmt.Sprintf("%d%s%s%s", FormatTimestamp(time.Now()), c.APIKey, r.recvWindow, bodyString)
-		}
-
-		mac := hmac.New(sha256.New, []byte(c.SecretKey))
-		_, err = mac.Write([]byte(signatureBase))
-		if err != nil {
-			return err
-		}
-		signatureValue := fmt.Sprintf("%x", mac.Sum(nil))
-		header.Set(signatureKey, signatureValue)
+		hmac256 := hmac.New(sha256.New, []byte(c.APISecret))
+		hmac256.Write(signatureBase)
+		signature := hex.EncodeToString(hmac256.Sum(nil))
+		header.Set(signatureKey, signature)
 	}
 	if queryString != "" {
 		fullURL = fmt.Sprintf("%s?%s", fullURL, queryString)
 	}
-	c.debug("full url: %s, body: %s", fullURL, bodyString)
+	c.debug("full url: %s, body: %s", fullURL, body)
 	r.fullURL = fullURL
-	r.header = header
 	r.body = body
+	r.header = header
 	return nil
 }
 
@@ -200,3 +192,26 @@ func (c *Client) callAPI(ctx context.Context, r *request, opts ...RequestOption)
 func (c *Client) NewServerTimeService() *ServerTime {
 	return &ServerTime{c: c}
 }
+
+// NewMarketKlineService Market Endpoints
+func (c *Client) NewMarketKlineService(klineType, category, symbol, interval string) *Klines {
+	return &Klines{
+		c:         c,
+		category:  category,
+		symbol:    symbol,
+		interval:  interval,
+		klineType: klineType,
+	}
+}
+
+// NewPlaceOrderService Trade Endpoints
+func (c *Client) NewPlaceOrderService(category, symbol, side, orderType, qty string) *Order {
+	return &Order{
+		c:         c,
+		category:  category,
+		symbol:    symbol,
+		side:      side,
+		orderType: orderType,
+		qty:       qty,
+	}
+}
diff --git a/consts.go b/consts.go
index e8f1889..02028cc 100644
--- a/consts.go
+++ b/consts.go
@@ -3,6 +3,10 @@ package bybit_connector
 const (
 	Name    = "bybit.api.go"
 	Version = "1.0.0"
+	// Https
+	MAINNET       = "https://api.bybit.com"
+	MAINNET_BACKT = "https://api.bytick.com"
+	TESTNET       = "https://api-testnet.bybit.com"
 	// WebSocket public channel - Mainnet
 	SPOT_MAINNET    = "wss://stream.bybit.com/v5/public/spot"
 	LINEAR_MAINNET  = "wss://stream.bybit.com/v5/public/linear"
@@ -29,5 +33,5 @@ const (
 	signatureKey  = "X-BAPI-SIGN"
 	apiRequestKey = "X-BAPI-API-KEY"
 	recvWindowKey = "X-BAPI-RECV-WINDOW"
-	signTypeKey   = "2"
+	signTypeKey   = "X-BAPI-SIGN-TYPE"
 )
diff --git a/examples/Trade/place_order.go b/examples/Trade/place_order.go
new file mode 100644
index 0000000..e640850
--- /dev/null
+++ b/examples/Trade/place_order.go
@@ -0,0 +1,21 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	bybit "github.com/wuhewuhe/bybit.go.api"
+)
+
+func main() {
+	PlaceOrder()
+}
+
+func PlaceOrder() {
+	client := bybit.NewBybitHttpClient("8wYkmpLsMg10eNQyPm", "Ouxc34myDnXvei54XsBZgoQzfGxO4bkr2Zsj", bybit.WithBaseURL(bybit.TESTNET))
+	orderResult, err := client.NewPlaceOrderService("linear", "XRPUSDT", "Buy", "Market", "10").Do(context.Background())
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	fmt.Println(bybit.PrettyPrint(orderResult))
+}
diff --git a/examples/market/market_kline.go b/examples/market/market_kline.go
new file mode 100644
index 0000000..579b9fe
--- /dev/null
+++ b/examples/market/market_kline.go
@@ -0,0 +1,24 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	bybit "github.com/wuhewuhe/bybit.go.api"
+)
+
+func main() {
+	MarketKline()
+}
+
+func MarketKline() {
+
+	client := bybit.NewBybitHttpClient("", "")
+
+	// NewServerTimeService
+	marketKline, err := client.NewMarketKlineService("premium-index-price-kline", "linear", "BTCUSDT", "1").Limit(10).Do(context.Background())
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	fmt.Println(bybit.PrettyPrint(marketKline))
+}
diff --git a/market.go b/market.go
index aba27bd..b519089 100644
--- a/market.go
+++ b/market.go
@@ -34,3 +34,80 @@ func (s *ServerTime) Do(ctx context.Context, opts ...RequestOption) (res *Server
 	}
 	return res, nil
 }
+
+type MarketKlineCandle struct {
+	StartTime  string `json:"startTime"`
+	OpenPrice  string `json:"openPrice"`
+	HighPrice  string `json:"highPrice"`
+	LowPrice   string `json:"lowPrice"`
+	ClosePrice string `json:"closePrice"`
+	Volume     string `json:"volume"`
+	Turnover   string `json:"turnover"`
+}
+
+type MarketKlineResponse struct {
+	Category string              `json:"category"`
+	Symbol   string              `json:"symbol"`
+	List     []MarketKlineCandle `json:"list"`
+}
+
+// Klines Market Kline (GET /v5/market/kline)
+type Klines struct {
+	c         *Client
+	klineType string
+	category  string
+	symbol    string
+	interval  string
+	limit     *int
+	start     *uint64
+	end       *uint64
+}
+
+// Limit set limit
+func (s *Klines) Limit(limit int) *Klines {
+	s.limit = &limit
+	return s
+}
+
+// Start set startTime
+func (s *Klines) Start(startTime uint64) *Klines {
+	s.start = &startTime
+	return s
+}
+
+// End set endTime
+func (s *Klines) End(endTime uint64) *Klines {
+	s.end = &endTime
+	return s
+}
+
+// Do Send the request
+func (s *Klines) Do(ctx context.Context, opts ...RequestOption) (res *ServerResponse, err error) {
+	r := &request{
+		method:   http.MethodGet,
+		endpoint: "/v5/market/" + s.klineType,
+		secType:  secTypeNone,
+	}
+	r.setParam("category", s.category)
+	r.setParam("symbol", s.symbol)
+	r.setParam("interval", s.interval)
+	if s.limit != nil {
+		r.setParam("limit", *s.limit)
+	}
+	if s.start != nil {
+		r.setParam("start", *s.start)
+	}
+	if s.end != nil {
+		r.setParam("end", *s.end)
+	}
+	data, err := s.c.callAPI(ctx, r, opts...)
+	if err != nil {
+		return nil, err
+	}
+	res = new(ServerResponse)
+	err = json.Unmarshal(data, res)
+	if err != nil {
+		return nil, err
+	}
+	return res, nil
+}
diff --git a/request.go b/request.go
index da54f9a..49ecd9e 100644
--- a/request.go
+++ b/request.go
@@ -1,8 +1,10 @@
 package bybit_connector
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
+	"log"
 	"net/http"
 	"net/url"
 )
@@ -21,12 +23,12 @@ type request struct {
 	method     string
 	endpoint   string
 	query      url.Values
-	form       url.Values
 	recvWindow string
 	secType    secType
 	header     http.Header
-	body       io.Reader
+	params     []byte
 	fullURL    string
+	body       io.Reader
 }
 
 // addParam add param with key/value to query string
@@ -47,11 +49,20 @@ func (r *request) setParam(key string, value interface{}) *request {
 	return r
 }
 
-// setParams set params with key/values to query string
+// setParams set params with key/values to query string or body
 func (r *request) setParams(m params) *request {
-	for k, v := range m {
-		r.setParam(k, v)
+	if r.method == http.MethodGet {
+		for k, v := range m {
+			r.setParam(k, v)
+		}
+	} else if r.method == http.MethodPost {
+		jsonData, err := json.Marshal(m)
+		if err != nil {
+			log.Fatal(err)
+		}
+		r.params = jsonData
 	}
+
 	return r
 }
 
@@ -59,13 +70,10 @@ func (r *request) validate() (err error) {
 	if r.query == nil {
 		r.query = url.Values{}
 	}
-	if r.form == nil {
-		r.form = url.Values{}
-	}
 	return nil
 }
 
-// Append `WithRecvWindow(insert_recvwindow)` to request to modify the default recvWindow value
+// WithRecvWindow Append `WithRecvWindow(insert_recvWindow)` to request to modify the default recvWindow value
 func WithRecvWindow(recvWindow string) RequestOption {
 	return func(r *request) {
 		r.recvWindow = recvWindow
diff --git a/trade.go b/trade.go
index 06c9e41..530c031 100644
--- a/trade.go
+++ b/trade.go
@@ -1 +1,251 @@
 package bybit_connector
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+)
+
+type OrderResult struct {
+	OrderId     string `json:"orderId"`
+	OrderLinkId string `json:"orderLinkId"`
+}
+
+type Order struct {
+	c                *Client
+	category         string
+	symbol           string
+	isLeverage       *int
+	side             string
+	orderType        string
+	qty              string
+	price            *string
+	triggerDirection *int
+	orderFilter      *string
+	triggerPrice     *string
+	triggerBy        *string
+	orderIv          *string
+	timeInForce      *string
+	positionIdx      *int
+	orderLinkId      *string
+	takeProfit       *string
+	stopLoss         *string
+	tpTriggerBy      *string
+	slTriggerBy      *string
+	reduceOnly       *bool
+	closeOnTrigger   *bool
+	smpType          *string
+	mmp              *bool
+	tpslMode         *string
+	tpLimitPrice     *string
+	slLimitPrice     *string
+	tpOrderType      *string
+	slOrderType      *string
+}
+
+func (o *Order) TimeInForce(tif string) *Order {
+	o.timeInForce = &tif
+	return o
+}
+
+func (s *Order) IsLeverage(isLeverage int) *Order {
+	s.isLeverage = &isLeverage
+	return s
+}
+
+func (s *Order) TriggerPrice(triggerPrice string) *Order {
+	s.triggerPrice = &triggerPrice
+	return s
+}
+
+func (s *Order) OrderLinkId(orderLinkId string) *Order {
+	s.orderLinkId = &orderLinkId
+	return s
+}
+
+func (o *Order) Price(price string) *Order {
+	o.price = &price
+	return o
+}
+
+func (o *Order) TriggerDirection(direction int) *Order {
+	o.triggerDirection = &direction
+	return o
+}
+
+func (o *Order) OrderFilter(filter string) *Order {
+	o.orderFilter = &filter
+	return o
+}
+
+func (o *Order) TriggerBy(triggerBy string) *Order {
+	o.triggerBy = &triggerBy
+	return o
+}
+
+func (o *Order) OrderIv(iv string) *Order {
+	o.orderIv = &iv
+	return o
+}
+
+func (o *Order) PositionIdx(idx int) *Order {
+	o.positionIdx = &idx
+	return o
+}
+
+func (o *Order) TakeProfit(profit string) *Order {
+	o.takeProfit = &profit
+	return o
+}
+
+func (o *Order) StopLoss(loss string) *Order {
+	o.stopLoss = &loss
+	return o
+}
+
+func (o *Order) TpTriggerBy(triggerBy string) *Order {
+	o.tpTriggerBy = &triggerBy
+	return o
+}
+
+func (o *Order) SlTriggerBy(triggerBy string) *Order {
+	o.slTriggerBy = &triggerBy
+	return o
+}
+
+func (o *Order) ReduceOnly(reduce bool) *Order {
+	o.reduceOnly = &reduce
+	return o
+}
+
+func (o *Order) CloseOnTrigger(close bool) *Order {
+	o.closeOnTrigger = &close
+	return o
+}
+
+func (o *Order) SmpType(smp string) *Order {
+	o.smpType = &smp
+	return o
+}
+
+func (o *Order) Mmp(mmp bool) *Order {
+	o.mmp = &mmp
+	return o
+}
+
+func (o *Order) TpslMode(mode string) *Order {
+	o.tpslMode = &mode
+	return o
+}
+
+func (o *Order) TpLimitPrice(price string) *Order {
+	o.tpLimitPrice = &price
+	return o
+}
+
+func (o *Order) SlLimitPrice(price string) *Order {
+	o.slLimitPrice = &price
+	return o
+}
+
+func (o *Order) TpOrderType(orderType string) *Order {
+	o.tpOrderType = &orderType
+	return o
+}
+
+func (o *Order) SlOrderType(orderType string) *Order {
+	o.slOrderType = &orderType
+	return o
+}
+
+func (s *Order) Do(ctx context.Context, opts ...RequestOption) (*ServerResponse, error) {
+	r := &request{
+		method:   http.MethodPost,
+		endpoint: "/v5/order/create",
+		secType:  secTypeSigned,
+	}
+	m := params{
+		"category":  s.category,
+		"symbol":    s.symbol,
+		"side":      s.side,
+		"orderType": s.orderType,
+		"qty":       s.qty,
+	}
+	if s.price != nil {
+		m["price"] = *s.price
+	}
+	if s.triggerDirection != nil {
+		m["triggerDirection"] = *s.triggerDirection
+	}
+	if s.orderFilter != nil {
+		m["orderFilter"] = *s.orderFilter
+	}
+	if s.triggerPrice != nil {
+		m["triggerPrice"] = *s.triggerPrice
+	}
+	if s.triggerBy != nil {
+		m["triggerBy"] = *s.triggerBy
+	}
+	if s.orderIv != nil {
+		m["orderIv"] = *s.orderIv
+	}
+	if s.timeInForce != nil {
+		m["timeInForce"] = *s.timeInForce
+	}
+	if s.positionIdx != nil {
+		m["positionIdx"] = *s.positionIdx
+	}
+	if s.orderLinkId != nil {
+		m["orderLinkId"] = *s.orderLinkId
+	}
+	if s.takeProfit != nil {
+		m["takeProfit"] = *s.takeProfit
+	}
+	if s.stopLoss != nil {
+		m["stopLoss"] = *s.stopLoss
+	}
+	if s.tpTriggerBy != nil {
+		m["tpTriggerBy"] = *s.tpTriggerBy
+	}
+	if s.slTriggerBy != nil {
+		m["slTriggerBy"] = *s.slTriggerBy
+	}
+	if s.reduceOnly != nil {
+		m["reduceOnly"] = *s.reduceOnly
+	}
+	if s.closeOnTrigger != nil {
+		m["closeOnTrigger"] = *s.closeOnTrigger
+	}
+	if s.smpType != nil {
+		m["smpType"] = *s.smpType
+	}
+	if s.mmp != nil {
+		m["mmp"] = *s.mmp
+	}
+	if s.tpslMode != nil {
+		m["tpslMode"] = *s.tpslMode
+	}
+	if s.tpLimitPrice != nil {
+		m["tpLimitPrice"] = *s.tpLimitPrice
+	}
+	if s.slLimitPrice != nil {
+		m["slLimitPrice"] = *s.slLimitPrice
+	}
+	if s.tpOrderType != nil {
+		m["tpOrderType"] = *s.tpOrderType
+	}
+	if s.slOrderType != nil {
+		m["slOrderType"] = *s.slOrderType
+	}
+	r.setParams(m)
+	data, err := s.c.callAPI(ctx, r, opts...)
+	if err != nil {
+		return nil, err
+	}
+	res := new(ServerResponse)
+	err = json.Unmarshal(data, res)
+	if err != nil {
+		return nil, err
+	}
+	return res, nil
+}