imageshack.usdownload your gif to your pc, MAKE SURE IT WORKS on your pc. Then upload it on imageshack OR
www.photobucket.com which I suggest more
Those sites gonna give you a link UNDER your picture saying like
html code
img code
clikc to the text at the right side of img code (I mean copy the link there with [ img] [ /img] code, whit the img's) and go to the PROFILE on this site. find where your avatar thing is. Its forum profile info. CHOOSE "I HAVE MY OWN PIC"
Then copy the link there without the [ img] s.
if that doesnt work
choose I will upload my own picture, then browse where your gif is, say ok or open or whatever. Itll upload, wait till it finished
THIS SHOULD DO if this doesnt do you have a broken gif