The technique in this entry is simple: make a small colored spot with a brush and use the smudge tool to draw it into the shape you want.
Using the non-colour beside your coloured spot can act like black paint to make your line darker. Mixing them up slightly will give you a darker colour.
Using the non-colour beside your coloured spot can act like black paint to make your line darker. Mixing them up slightly will give you a darker colour.