I did this drawing of Sugar Glider a while ago now and set it to one side for Photoshopping. I wanted to learn a few new things about colouring and using textures and found this tutorial massively helpful. Especially using cmd+alt+2 to select the white areas of a drawing to easily separate the line art. It's those little things that save you a load of clicks and keystrokes. Secondly, filling in the areas you want to colour with separate blocks of colour so you can easily switch them if necessary was rather useful.
I took my textures from Lost and Taken, just for speed, but they have a good selection of freebies if you check out their gallery. Finally, I added a vignette and adapted the last few stages of the tutorial to get it to fit in with the colour scheme and mask the fact that I hadn't drawn all of SG's arms. I'm really pleased with the results, but still think I've got a long way to go with colour. Anyway, here's the before and after.