http://kitted.deviantart.com/art/DITHERING-TUTORIAL-Basics-69747353

http://www.furcadia.pixelovely.com/dithertut.html

:)

I really tried to use dithering on this but since im really new to this technique I found it difficult to use. Can you guide me to some good dithering tutorials. Thanks

Looking good!  Some parts could use some dithering to make the colors look smoother, but if you want to keep the clean feel of the piece, that's fine.  I'm interested to see what the face would look like!