ive figured it out, if any1's interested on how to do it let me know

 

first you need to resize your pic to 96x96 or else it wont work and it needs to be a png file also when you name the file make sure the extension is .png for som reason it wudnt work unless it had the extension.

 

when you log in, double-tap on the picture.

 

oh cheers, how stupid could i be