Photobucket vid to myspace default?

i had a video on my computer and i wantd to turn it to a gif so i can juss upload it on myspace i tried that n now tha video wont even sho up on my computer but i had it on photobucket which is kinda harder because i cant save it to my computer..so i was wondering how can i get it to b my myspace default its 3 seconds by tha way because the orignal video was 7 but that was too long =[