Did you see the documentation in the appstore?
Configuration
All objects that you would like to log need to have the AuditTrail.AudittrailSuperClass as a superclass except the subclasses of the System.User object. To log subclasses of the System.User object: Add the 'BCoUser' microflow in a 'before commit' event of the subclass and the 'BDeUser' microflow in a 'before delete' event of the subclass. These microflows can be found in the folder: 'System User logging' Add the 'AuditTrailOverview' form to your navigation.