It's really hard to give you any proper advice on how to apply stuff since I don't have a clue what your friend is!
Is he some kind of an insect?
An advice is also to not hesitate into everything at one time. Believe me, animation is not fun when there is a lot of stuff that is not solved yet.
Try concentrating on one thing at a time and then move on.
The first thing I think of when I see the flying green insect/dwarf is that you need to clean up the lines. There is a big different, believe me or not, between 2 pixels and 3 pixels.
So you have to work with your curves, like yaomon17 did, the face he redrew got a lot more cleaner shapes and rounder corners. Try to apply that before you start colouring and
animating.