required programs quickplay you can download it here
http://www.apple.com/quicktime/download/1. open what animation you want
2.click files
3. click export animation
4.save as animated GIF
5.make frame delay 3 4 or 5 these are the best options
6. change the 2 percents to pixels
7.the pixels will have 350 and 250 change both to 75
8. click export
9.change avatar normally to it
hope i helped