When drawing the eyebrow, use the bone above the eye socket as a guide for the shape of the eyebrow.
To create a sunken zombie eye, use your finger to blot red greasepaint along the bottom of the eye socket and around the top of the lid.
Then use a paintbrush to outline the bottom of the eye socket in black.
If you want to be gory you can create an eye out of a small balloon by filling it with strawberry jam until large enough for the eye socket.
Aviators have a metal frame, housing a lens which is typically around two or three times the size of the eye socket.