Search for your community (either on the „Communities I Own“ tab or „Available Communities“
Method 1:
When you found your community, select „Assign Members“ in the Actions Menu, to assign new Members to the community.
Click on „available“ and search for the new user.
Click the checkbox in front of the users name you want to add to the community.
Click on „Update associations“
Click the „Current“ tab
Click on „Assign User Roles“ behind the user name you just added (it might be needed to go to page two, three, etc.)
Check the checkboxes in front of the roles you want to give the user (hint: community owner for professors, post-docs, phd students, etc.; modul administrator for people managing course contents, as hiwis). See also Electures Roles
Click on „Update Associations“
You are done.
Method 2:
Or select „Assign User Role“ to give a user certain permissions. (This can also be done in the „Assign Members“ menu)