1. This is the raw scan. It's a lot cleaner than my usual scans, because I did it with a dark 4B pencil. Nevertheless, the image is very low contrast.

2. I use the levels and curves adjustments and other tricks to get the line art darker and clearer. I use a soft brush set to linear dodge blend mode and white color to erase the smudges. The fish feels a bit too long, so I shortened it a little, which involved repainting part of the pattern.

3. I did a bunch of quick experiments, to figure out the general color scheme (not shown). I set the line art layer blend mode to linear burn (for a slightly spicier effect than multiply), and underneath I create a new flat color layer. On this new layer I create a mask, then use the polygonal lasso tool to define first the shape of the fish, then the different colors of the fish. Sometimes I use the pencil tool instead to define these shapes.

4. Here's where the fun starts - I select one of the colors and use it as the mask of a new layer, a photographic texture. In this case, it's a photo of a puddle of dye, which I use quite a lot in my work.

5. The rest of the textures - two types of rust, a gritty metal wall, and an art room floor splattered with canvas primer.

6. Now I add a bunch of adjustment layers to each of the rust layers, tweaking their colors and brightness until they are more or less complimentary. I also paint the two kids, and add a light background for depth, also with a texture.

7. The final touches - I make the outlines colored (slightly green), color balance the whole fish, and paint some new white decorative designs. Done!