Below is the link to the program you use to change your avi picture. Just share your sim to the launcher (DON'T upload it yet) and open the Upload Image Changer. Your sim will be under the "Browse" option. Make sure your picture is 512x512, and a .PNG file. It's as easy as that. =]
Comments
http://forum.thesims3.com/jforum/posts/list/112017.page
"If you don't talk to your cat about catnip... who will?"
"Before you criticize someone, you should walk a mile in their shoes.
That way, when you criticize them, you're a mile away and you have their shoes."
http://www.zindasgoldensims.com/uic/