Deanna R. answered 04/11/19
Professional Digital and Traditional Artist
Are you asking how we personally organize them or how you move them around in the layer tool?
If you're wanting to move them around, just click and hold them with the mouse or tablet pen, then slide up and down to move them where you want.
If you're asking how we personally organize them, I like to sort the background, foreground, and midground (usually the character) into groups, then from there have layers for each "big" element. For a character, this usually means one layer for the pants, with the shirt layer over it and the socks/gloves or whatever layer under it. Hair is almost always the top layer and skin is almost always the bottom layer. If you'd like more elaboration please let me know!