How to get an avatar and signature:

At the top of the screen, you'll see something called profile. Click on that, and it'll take you to your profile. Then, click on the avatar button there. Just click browse then, and upload one of your pics to be your avatar! The signature button is right next to the avatar, and is muche asier. All you do is type something, click save, and valla! You have a signature.

Hope this helps-