you need to either have 500 posts for a usertitle change, 1337 posts for a usertitle image, become a staff member (allows you to set your title yourself, bigger avatar & profile restrictions) , or you can always donate $25 or more and get the ability to change your title yourself (plus bigger avatar & profile restrictions).
You need to post more to get member level 1, which allows bigger avatar/profile restrictions.
https://www.mpgh.net/forum/profile.php?do=editoptions
at the very bottom