how to edit Categories

[Shaked]

hello guys im back i have question about editing the Categories

i want to put in each categorie deiffrent Photo \ banner i uploaded some pics so i can show you

oke this is like in my forum now :

you see guys that all the pictures are the same ? i want to use each categorie or sub categorie in diffrent image or banner

example for some web like i want :

if some one can tell me how can i do that it will be So Great

thanks alot