How to move New Members to a New Usergroup

[Snowball1]

I have been trying all day to move newly registered members to a new usergroup but it doesn't work. Anytime someone registers on my forum he automatically becomes a member of the"registered" usergroup. However, i will like to create a new usergroup so that any user who registers from now onwards will not become a member of the "registered usergroup but instead will automatically become a member of the newly created usergroup. Is there a way I can do this? I tried using the promotion but that doesn't work. Thanks very much:)