I got bored and did another (hope u dont mind)
The principals are pretty much the same and again was done in 3 stages:
Quatriomite Original


Stage 1: (1st layer, Background Coloring)


Stage 2: (2nd layer(copy of 1st stage)Blotches Added, Layer reduced to 75% opacity)


Final Stage: (3rd layer, Detials, Highlights and Touchups)


PSD again can be found Here

Generally when colouring i will use those 3 basic stages and maybe add more depending on the complexity of the colouring. Each picture also took about 20-40mins to complete.

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