I have trouble determining what is the right wind direction. If I'm sitting in my spot with my back facing the east, and I am expecting the deer to come out of the west, what should the wind direction be?
Given your scenario, you would want the wind coming out of the West -- blowing toward you from the direction you expect the deer to come. Your scent would then be carried behind you and away from the approaching deer.
Deer are where they are, not where you think they should be.
Deer have great noses. . . . .so wind direction is pretty important. As Strut&Rut states keep it in your face or no more than 45deg. When you are hunting on the ground your scent will stay low and even a little bit can make them change paths.