You are free to use to color this to your preference ^^ Just link to this and link me to your art so i can see it :D

Now how best to color it is to (in photoshop at least) set this on the top layer, and set the layer to multiply
this will make the darker area's stay on top and the white area's to show the color, so basicly this is the lineart, there is some shading and so , well make it look cool i'd say ;)