Brush is by default grayscale. Set layer to multiply and color in a layer underneith for color. Angle turns with direction of line and changes size with pressure.
I wanted to make a dragon scale brush, so I drew one.This brush is by default only in grayscale because it was the only way I could keep the detail and contrast. But for coloring you can set this layer to multiply and then color in a new layer underneith like my example.

In action:
