Now it's time to add textures to the alien. On the left, I have my texture map. In Photoshop for some of the parts like the skin, I just used simple colors and then applied a general noisy texture over it to make it seem less flat. For most of the rest though, I found textures online and used those. That included metal for the armor pieces, leather for the belt, fabric for the shirt and pants, etc.
After placing a texture in Photoshop, I exported it into Maya to see how it looked on the alien. Then I adjusted the size of the texture if it wasn't looking right along with color and brightness. After I was ok with the texture, I went back into Photoshop and drew in shadows and highlights to enhance the look. This involved a little guesswork so there was a lot of back and forth between the two programs to get the right look. On the top left, you can see the textures by themselves. Next to that you can see what I drew in by hand. It was a lot of work but it turned out well. Below you can see the alien with basic textures and then with all the extra stuff I painted on. It's pretty impressive what you can do to create the illusion of light and shadow.