Pamoya hosts three kinds of groups. Open groups where membership requests are accepted immediately, invite only groups where membership must be created by an administrator (you can not request membership) and moderated groups where membership requests must be approved.
Assuming you are logged in to Pamoya Beta.
Click "Pamoya Groups" on the main menu.
To join an open group, click the "join" link behind the group of interest. On the page that opens, click "Join". You are now a member.
To join a moderated group, click the "request membership" link behind the group of interest. On the page that opens, provide details as to why you should be allowed membership and click "Join". After some time you will be notified by e-mail whether you are accepted or not.