Choose your picture. Some use screenshots in game, others use something they really like, a movie for example. As long as it is not yourself or raises the rating of the site then you can use just about anything else.
You will need to be in CAS and share a new sim (not a household, just a sim). Before you upload to the site, go into the program above and find the sim you want to upload. Replace the sim with a 512x512 .png file and then upload.
Come on to the site and you can either go into your studio and select, make this my avi or go into your Page, Edit profile and change it from there.
@VALLEX - Good to know. Was just checking in with everyone and to let them know of the new thread!