Choose an off center light source so that your lighting isn’t symmetrical
2 3 2 1 2
When shading a compound curve, follow the same zone order, but bend the zones to the surface.
Start with color blocking
Shift shadows in hue a little bit, can be warmer or cooler.
look for shadows around the centerline as well as from top to bottom from occlusion.
inside of holes is a mirror of the outside shading order
Highlight the top face separately, slightly biased toward the