How would i
 

Well im wanting my members who get to Platinum rank to be able to change colour, I came to the concept they'd join a public group then relised that would allow anyone to do it? so how would i make it so they can change the colours of there names without having a admin do it?
Ross

Create a new usergroup and add what you want to the Username HTML Markup section.

For example:
Then create a promotion to move them to that usergroup based on the criteria you want. When they reach that criteria, the forum will automatically move them when the User Promotions cron runs.

nono, I need to find how they would join the usergroup by like Group memberships ect

Is it a paid membership or just like if you have certain amount of posts you get the platinum ranks?

If its a paid membership you could go through subscriptions and when they buy the subscriptions it will automatically put them in the user group of your choice thus changing the color. If it is for members with a certain number of post (or something like that) promotions would really be the easiest bet. You don't have to mess with anything once its done and you can input if its by their post count, rep point ect. If this is not what your looking for please explain. This is one of the areas of VB I am good at lol.

The forum automatically changes the usergroup when the speified criteria is met. I don't see any other way of doing what you want.