To draw our ceiling, we're going to use the Rectangular Marquee Tool. We're going to highlight the area in which the ceiling is and it doesn't have to be perfect. And we're going to go down to our color and adjust the color for our ceiling. So select a few shades lighter, and hit OK. Let me go to Layer, New fill layer gradient. Okay. And then adjust our angle to be 90 degrees going in the opposite direction.

So the light is forecasting and coming off the back wall. Hit OK. Now you can see you can adjust this feeling so that it looks realistic