What this tutorial is about:
Add new user and assign access rights (editors)
Good to know:
Only Site-Owners can add users and grant user permissions
The following four roles should always be assigned to users (no distinction necessary between user categories): COMA Author, COMA Editor, COMA Publisher, Dockbar
Nota bene: In order for Site-Owners to grant user permissions to any person, this person must have logged on to Liferay beforehand.