Well, think of a page, the background is the first layer being all blank and 2nd layer are panels.
Later on, I make a layer for one of the panels should I include characters I will make a layer for sketches, another for outlines, the next layer under the outline layer are one color and use another layer over that colored layer for clipping mask so that the rest of the colors will be placed on the colored layer and not out side of it. That would colored layers for clothings, and later under it is the layer for colored skin, eyes, and hair and later all of the above are decreased black opacity colors for shadows as a secondary color.
Next is the background behind the characters, the same as always, sketch layer, outline layer, colored layer with two to three clipping mask layers and should there be a sky that would be the main background with it's on layers; the color of the sky; day/night, moon/sun, stars/clouds/rain.
Even after all that, I need to add a brush that might resemble fogs, dusts, or rain drips as the main front or and extra layer behind the characters.
So get this
1- One layer for the panel.
2- Sketch layer for characters.
3- Outline layer for characters.
4- Colored layer for characters.
5- 3 or 4 clipping mask layers over the colored layers as secondary colors.
6- Sketch layer for backgrounds.
7- Outline layer for the backgrounds.
8- Colored layer for the background.
9- Two or three clipping mask layers over the colored layers as secondary colors.
10- If there is going to be a sky than that is the main background, use any colors for day or night.
11- Another layer over the day/night layer for the moon/sun.
12- Next layer for star/clouds or both.
13- the next is an extra whether you want to add a layer of dust/fog/ or dripping rain.
That's about 16-18 layer for one panel. So imagine for the entire page. Should there be 10 panels a page then I must be doing 161-181 layers a page (including the black background behind the panels).