ok

Its not that you 'have to' make BG trans its just that it looks better and more pro when you do ;)

Maybe its just better to make a whole new walking animation and take what you learned here to make it better.

and i have forget about the BG. I did it in MS Paint and i forget to put transparence in another program  . I'll put the transparence on BG when i remake the animation

ok, i'll make another animation later 

Is the BG needed? Trans BG on sprites is better ;)

The arms and legs should move in opposite direction (when left leg is on the front, left arm is on the back). Walking like that is really bad for the skeleton!

Also, that green background should be removed!