http://www.digitaltutors.com/tutorial/1417-Painting-Textures-for-Game-Characters-in-Photoshop

When texturing game assets, often times there are several challenges to overcome and variables to consider. In this course, we will talk about some of these as we walk through texturing a character for the current generation of game consoles. After setting up our Photoshop file, we’ll get started painting the color map for our character.

Using a combination of painting techniques and layer styles, we’ll focus first on his clothing but eventually move to the other areas of the character including his skin, hair and a pass of dirt to make our character feel more natural. After finishing off the color map, we’ll move on and learn how we can quickly create a specular map for our character by repurposing many of our color textures. To wrap this course up, we will learn how to paint a transparency map that can be used to mask portions of the hair geometry for our game character. After finishing this course, you will not only have a fully textured game character but you’ll also have a good idea how to overcome many of the challenges that come with this type of project.