Coloring with level & Layers

Hi-res scan of initial drawing.
Painted layer for background forest with textured brushes followed by some mild masking.
Adjustment layer (levels) used to create highlights and shadows/

Click to see the Levels Adjustment and Mask…

Adjustments are made mostly to bring the ends of the histogram towards the center. Because this is a night-time scene I darkened the midpoint as well.
Details of masking adjustments made with Burn/dodge tools and paintbrush.
Colors painted on a separate “color” layer, set to color.
Vector color shape set to multiply then masked.
Top layer color effects painted on top with a normal brush strokes.

Final Art.