My basic process for digital rendering

Here is my basic process for rendering an illustration in PS CS4.

My initial sketches are always very, very rough. This piece is for an adult short story: Landlady by Roald Dahl.

Then I started with value study by using a big, textured brush. At this stage, I did't worry about colors, because I will add color later with a small trick.

I don't like working with too many layers, so only the backround(usually a grey color), initial sketch, and the painting layer.

At first I had the landlady standing behind the door, but then I changed the composition, because I wanted the viewer to focus on the young man's gesture, expression, and feeling.

Now let's talk about the trick. I added a new adjustment/curve layer at the top. Note: click "RGB", at the drop down menu, choose blue, red, or green one at a time, and adjust the curve to see how it affects the image. By using this function, you can give the image a new color.