To add or remove members from a group:
Notes:
You can't add outside users to a group. Outside users' names appear in purple text, and they have icons () after their names. For more information on outside users, see Outside Users.
Some system configurations prevent you from removing yourself from a group. For example, you can't remove yourself from a group that is synced up with a group in your LDAP directory.
If you remove yourself from a group, you also remove yourself from every item the group is a member of. After you remove yourself from an item, you can't add yourself back in. You must ask another member to do that for you.