You don't need a photobucket account. You just need to do the following:
1) Click profile. (Or right-click, and hit open in new window or tab)
2) Click on the avatar link. It was hard for me to find so if you can't find it, hit Ctrl F and type in "avatar."
3) Find "Upload an Avatar from your computer" and hit browse. Locate your photo and hit open.
4) Hit save, at the bottom, and you're done.
Hope this helps.