Ok well, I am guessing you don't have a scanner. The image quality isn't so good since you took this with a camera it appears.

Anyway, you should work on your anatomy a bit. His limbs are short and fat, and his head is a bit oblonged and oversized. You should check out "The Official Artist Advice Thread" to find some things that could be helpful to you. You seem to be able to draw the basic 'ninja' suit good, you just need to learn a bit about human anatomy now.