/ic/ - Artwork/Critique

so, I want to work on desaturated, high-contrast black/white stuff, and I was wondering, how should I go about filling in large portions of deep blacks like shadows and such? Whenever I do it it looks very unclean with brush lines everywhere, basically I want it to look more uniform and clean.

pic related, if you look at the characters hair, it's flawlessly black, no indication of a bursh or pen going back and fourth over the area