Colouring in Illustration - Values First, Hues Later

I love this Illustration, and from what I could tell, a lot of people love it too. I find it funny that they do, because this was my first attempt at something that I haven't tried before. Instead of choosing the palette and painting under and over the line work, as I usually do, I decided to first get all the values right, and then color underneath those values. I thought I was going to drive myself crazy and cry at the hours spent doing such a horrible abomination, but I'm pretty happy with the result!

So I started like I always start, and like everyone else start: SKETCH

Once I was happy with the sketch, I traced all the outlines. This is pretty common, obviously. Usually I clean the sketch just a bit with the eraser and paint under it, or over it, but since the outline is going to be above all (or most) color layers, I did them all again. Even though you can't tell here, all of this line work is split in several layers in order of depth, like Disney artists did with the deep canvas.

Here is where the real challenge began. First I filled the line work with white (you don't see it in the image, but it's there) so i could create a clipped layer on top of the white fill and not go out of the borders. To create a clipping layer in Photoshop put your mouse between two layers, and press Alt+click. The layer on the bottom will become the parent layer, and the one on top will be the clipped one. You can clip several layers on one parent.

Once I had all the clipped layers I needed I started shading! The most challenging part was to shade while considering how the color of the thing I'm painting is going to affect what I'm shading at the moment. Is it going to be too dark? too light? Is it going to look wrong?

You can see the monkeys look blue, because a black shadow was just too dark for the brown shades in the monkeys. So with a blue shadow and the layer set to multiply, the color of the monkeys and the shadows mixed nice.