1. Function
The connection of ServiceNow is only available for the Enterprise Editions.
The ServiceNow platform allows the mapping and automation of various workflows (keyword ITIL), including the forwarding of Checkmk notifications to users.
The integration runs using the instance URL and login data.
2. Configuring ServiceNow
A special configuration within ServiceNow is not required, only the instance URL (possibly in the form of a custom URL) and user data must be known. The user must have the role itil in ServiceNow.
3. Configuration in Checkmk
You have already learned how to set up Checkmk notifications in general in the article about notifications. To connect ServiceNow, now proceed as follows in Checkmk:
For the Notification Method choose Servicenow (Enterprise only).
For the ServiceNow URL enter your instance URL.
Add the user name and password of the creating user.
Under Caller ID add the user name of the concerned user. It is recommended to use the same user name as creating and concerned user. See the Checkmk inline help for more detailed information.

All other options are only used to design the notification content. For the two ServiceNow-specific options Urgency and Impact you can find in the inline help of Checkmk links to the respective entries of the ServiceNow documentation.
For testing you can use the Fake check results and Custom notification commands.