For the Slack API Client use:
go get github.com/nlopes/slack
Slack has two different kinds of bot users: app bots and custom bots. Recommended sticking with app bots.
In order to create Bot as a SlackApp: https://api.slack.com/apps
In order to create custom bots: Head to https://$YOUR_ORG.slack.com/apps/A0F7YS25R-bots to get to the Bots app page and get Slack setup properly.
In the token.json, replace "YOUR_TOKEN" with your token "xxxx-.......-..............."
go run main.go
Write to your bot "@your_bot hello" in Slack. If you write to bot in private messages you don`t need to use "@your_bot". Just write to him and he will understand you! :)
Also possible to use "hi", "Hi", "hello", "Hello", "hey", "Hey"