The dark circle in the right corner is light bulb I chose to put the highlight on his right shoulder this is where key light shines. I colored outside part. Did overlay and blurred it with Gaussian blur. Made new layer and colored white and did the same thing Gaussian blur and overlay. For last I colored green in the eye but I wanted it to be more fitting in the picture. So I blurred it.
I put the cast shadow in left arm. I also put bounce light in left leg you can see white at the outside part.