r := redis.NewClient(&redis.Options{
    Addr: mr.Addr(),
})

botstate.SetStorageClient(botstate.DefaultStorage(r))

var myClient botstate.Storager

...

botstate.SetStorageClient(myClient)

package main

import (
	"fmt"

	"github.com/go-redis/redis/v7"
	"github.com/gucastiliao/botstate"
)

func main() {
	redis := redis.NewClient(&redis.Options{
		Addr:     fmt.Sprintf("%s:%s", "127.0.0.1", "6379"),
		Password: "",
	})

	botstate.SetStorageClient(
		botstate.DefaultStorage(redis),
	)

	states := []botstate.State{
		{
			Name:     "start",
			Executes: Start,
			Next:     "add_product",
		},
		{
			Name:     "add_product",
			Executes: AddProduct,
			Callback: CallbackAddProduct,
			Next:     "confirmation",
		},
		{
			Name:     "confirmation",
			Executes: Confirmation,
		},
	}

	bot := botstate.New(states)
	bot.Data.User(111)

	bot.ExecuteState("start")
	msg := bot.GetMessages()
	fmt.Println(msg)
	// This print [Hello! Starting...]

	current, _ := bot.Data.GetCurrentState()
	// Current state now is -> add_product
	// Because value of State.Next

	bot.ExecuteState(current)
	msg = bot.GetMessages()
	fmt.Println(msg)
	// This print [Add Product...]

	current, _ = bot.Data.GetCurrentState()
	// Current state now is -> confirmation

	bot.ExecuteState(current)
	msg = bot.GetMessages()
	fmt.Println(msg)
	// This print I'm in callback now and [Confirmation ...]
	// The callback is defined in the previous state
	// And in this execution is called
	// If the callback return true, the execution continue and call Confirmation method
}

// botstate.Bot have access to current user's data
// and can manipulate it
func Start(bot *botstate.Bot) bool {
	bot.AddMessage([]string{
		"Hello!",
		"Starting...",
	})

	return true
}

func AddProduct(bot *botstate.Bot) bool {
	bot.AddMessage([]string{
		"Add Product...",
	})

	return true
}

func CallbackAddProduct(bot *botstate.Bot) bool {
	fmt.Println("I'm in callback now!")

	return true
}

func Confirmation(bot *botstate.Bot) bool {
	bot.AddMessage([]string{
		"Confirmation...",
	})

	bot.Data.ResetCurrentState()
	return true
}