Tutorials - Shading 2
This first technique uses the brush and smudge tools filter. It works best for large pieces of clothing. I usually use it for bottoms (skirts, pants).
First, create a new layer and draw the outline with the darkest colour
As in the previous tutorial, flood-fill the area with the third colour and select it with the magic wand (in the tool properties tab, set the tolerance to 1). Here, you cannot see the dotted lines around what I've selected because I've hidden them by going in Select>Show Marquee
Now, you need to click on the brush tip tab (if it's not on your screen, go to View>Brush Tip Tab) and select the fourth brush of the second row (refer to the image)
With that brush and the second colour, add some shading to the sides of the skirt. Do not put your pointer inside the outline of the piece of clothing. If you glide your mouse a pixel away from the article, there will still be some shading since the brush is so big.
Repeat with the first colour and a smaller brush (I've used the second brush of the second row.)
With the lightest colour and the second brush of the second row, add some highlight towards the middle. It doesn't matter if it looks strange: we'll arrange that later with the smudge tool.
Take the smudge tool and set the opacity to 60% (in the tool properties tab.) Sweep along the highlights and the shadows until you are happy with it (do not sweep from left to right) and that's it!
Here's the final doll. See my Shading 1 tutorial to find out how I made the top.