Using a web browser log into the forums. Find your account name in the top right corner. Click the drop down arrow and select control panel. You'll find the option there.
That's what I'm doing, but when I click my name, nothing happens. I'm using Google Chrome and IE. Any other ways around it?
Try Firefox. The admins are aware of problems, so I'm sure something will happen soon. Or use this link in the meantime: http://forums.toucharcade.com/usercp.php
I'll try FireFox later when I get on a PC that has it - just advising it's still not working on GC or IE.