In Slack Apps Dashboard create a new app in Button "New App".
Then, select "From an app manifest" option, and past the json app_manifest_example.json, of this root of this project. And change the <Your bot's display name> string, by your but name, and can do anything and <Your server url> by your server URL.
Then, click in create.
In Install your app click in the button with the label "Install to Workspace".
After this, do this:
Go to OAuth & Permissions screens and copy Bot User OAuth Token. Then this, you can past the token in SLACK_TOKEN env.
The last thing to do. Please, go to the channel you want to add the bot, and add her in "Integrations" path.
For copy the channel bot, just copy the link of url, or in desktop, click in copy, then copy link, in your channel.
The link is looks like: https://app.slack.com/client/SLACK_WORKSPACE_ID/CHANNEL_ID
Your channel is the last id, and copy her, and past in SLACK_CHANNEL env.
After this steps, you good to go, and can return to main documentation.