hey dude, for the values, use big brushes,, and block in the main shapes, the most important thing is that we get a feeling of solidity ! for that, we must feel that the body is lighted bythe same lighsource everywhere ( sounds obvious, but the comon mistake is that there is no harmony in the light, like each body part is lighted from a different light source ! ) keep in mind to block in the shapes, and to paint the whole body from the same light source, and it'll be ok !! keep it up !