a user request - usergroups setup help

[jazzyname]

I have tryed to create a requested user group.
But It shows up in a users CP --> Group Membership
as any one can join it freely...

I would like that they would need to post a story in which to be able to join that group freely.
If I select that it is public, which I would like that it is [ thus avalible to anyone] and that it is a request, But the manual is confusing.

Please help, I would like the usergroup to be a requested one.
Can someone give better detail than the manual

Thanks in advance.

jazz