Girl! I do CG all the time now. Look at my siggy! All CG done.
You want tips...I'll go into detail if just for you.
You have a good basic idea. Highlighting and shading. Though you don't have much contrast within the colors. Also starting with a solid base color helps. Generally the darker the better and working your way lighter. I kinda like a middle and go both ways lighter and darker...probably takes more time but that's how I do it.
Also if you want a more Cell shaded look try not to be too smooth.
Here's a nice tutorial site I used when I was first learning.
http://lian.exorsus.net/Also some nice art there.
3nodding