1. Login with the name u want to be a ghost 
2.Go to account info and click edit/create profile 
3.Then create another profile...it can be any name u want 
4.Then go to this site http://edit.profiles.yahoo.com/config/select_identity?.profsel=chat_pf_1&.src=chat&.done=http%3a//chat.yahoo.com/&prof_delete 5.click confirm delete