Very good, try using darker shading, buy a 9B pencil or use a black crayon to get the realy dark areas right, this will give them a lift. The drawing it's self is very good. A useful thing to try is to mix stlyes by adding black or a contast colour/s its called a spot. On this drawing you could show a red or green glow on the eyes or mouth. Well done.

thanks for the hint i will try that

thanks