Guide on setting up Slack notification in RAW 1.6

Does anyone have a complete guide on setting up notifications for Slack in Check_MK RAW v1.6? Should there be a notification user for Slack even though the Webhook-URL is typed in the notification rule?

Thanks in advance.

The guide to set up notifications to Slack can be found here: Notifications via Slack
In short, you just need to create an incoming webhook in Slack and make it known to Checkmk. There is no need to create a separate user. Messages from Checkmk appear under the user who created the webhook.