Once Act On It is installed and package licenses are assigned, users must be grouped into one of three permission levels, known as User Types:
Act On It uses a picklist field on the User record called: Act On It User Type. This picklist is what controls Act On It access.

When you update this field:
Changing or clearing the value automatically updates or removes permissions as well.

Tools such as the Salesforce Data Loader can be used to assign user types in bulk.
If you don’t see Act On It User Type on the user record, the field likely hasn’t been added to the page layout yet. A Salesforce Admin can add it in a few clicks:



Repeat steps 5–7 if multiple user page layouts are in use. Once added, return to the user record and refresh. The picklist should now be visible.