You mean avatar or an armatar? Armatars can be obtained by clicking on control panel and hitting the armatar tab. You should have 32 or more armatars depending on your AP. Avatars or outside picture aren't currently allowed.
Well, in the top right corner of the screen you should see your name, then right below your name you should see "control panel" click on it. Then kind of near the top of the screen you should see armatars, click on it. Then, choose the armatar you want and then go to the bottom of the page and click "update armatar"
