That's one tough exercise dude, making a lowpoly model out of a simple stylized character like that.
What's important here is to respect the global masses and the dynamic lines of your character :
[Blocked Image: http://kokosovar.free.fr/wilma.jpg]
Try to understand how it works in a global way before starting any detailing, i've drawn in red the masses and in blue the dynamic lines.
Be also very careful of the animation, add some edge lines at the articulations. And do not make them straight, make them follow the volume
I hope it helps and that it's not too late :x