Near the top right of the page you'll see the User Control Panel link, which takes you here:
http://drmcdougall.com//forums/ucp.phpOn the left-hand side of that page you'll see a column of links to set up your profile, board preferences, avatar, etc.
Be sure to click to save changes on each page you change. If you need help with anything, either check the FAQ link at the top of each page or just ask.