You can't just "put" the ninja on an already-made background. What i do is make a new layer for the background, change the "normal" above the new layer to "And", and paint out my background. I paint over the person in the drawing while I'm doing the background, and when I'm finished with the background, I erase the paint inside the figure so that it looks like the person was "put" onto the background. If you're still wondering about it, watch the animation on my "sexy cheetah" drawing, or memo me. Or, you can memo marcello and he'll probably give you a more detailed explanation.