So basically you see the circle with an X? Thats were the tail would be, but now heres the hard bit to explain. If you wanted to move the arm up you'd put it were the arm would start, so like the armpit for example. So amagine a body with no arms and no legs. you'd put an x on the body were the arms and legs would be, but only if your animating. So if i wanted to only animate the legs i'd keep the arms there and do a body without the legs. And on a different layer/Frame you'd draw the x and then make sure the x is not seen in the animation. and is covered, but everything you animate has to cover up the x. Then once you;ve animated the leg movement, copy and paste it in. This is only if your character isnt moving across the scene. So walking on the spot is fine for this method. Hopefully you understand what im talking about