This would have to be tidied up properly of cause.
The Lock Alpha is at the top of the layer box. Choose the layer you want to re-color and click Lock Alpha. Remeber to turn it OFF when erasing something.
What happens if you don't. If you go to lock and colour something near what you erased, you'll find your erased stuff coming back.
OK Layer wise you want to have it like this.
Lines
Shine/Light
Shade
Color/base/lock alpha layer. (Though you can lock alpha and recolor any layer)
BG (THIS DOES NOT GET TOUCHED _ What you can do with this layer is fill it white while you are drawing so you can see what you are doing.
The above would go in that order as the lines cover the colouring and shaded jaggy edges for a cleaner look.
The reason you don't do anything else is for these;
You can make your final image transparent. If your image doesn't have a background/BG
You can color easier without messing up your lines.
And in general the more lakers you use one for lines, one for shade etc, you can edit things easier.
Check how the layer system works in the Editable Oekaki.This is a good one to look at. Just click COLORMEIN at the bottom of the picture and have a look.
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