I decided to pick a reference that had a difficult lighting situation. This scene from Pulp Fiction is particularly hard to block out because of the number of primary and secondary light sources.
First, the direct but diffuse light coming in from the right. Second, the bounce light from the left, Thirdly and last, the upward source of light (this is from the glowing content of the case Vincent opens).
Yes, it takes three light sources to break an artist. Don't quote me. This here... This had me weeping like Marie at Golgotha.
Anyhow, here is another really short image montage of the process for the art process sl*ts out there. It takes one to know one...
If you what you see the finished work, click on the like below.