If you are logged in, you'll see a link over there to the right that says "my account". If you click that, you can edit your profile. In particular, you should go to the "questions" tab. You don't have to answer them, of course, but the site will be more fun if you do.

Speaking of fun, a number of you have figured out that you can post a small picture of yourself. If you haven't already done so, you can add a picture from the first page of your profile. Just look for the section that says "picture", towards the end of the profile page.