1. Open your room photo. I used this one: Apartament
2. Press Ctrl+L to open levels settings. Try to get something like this:
3. You can set lower values for "Gray Arrow" to get more darker image.
4. Image -> Adjustments -> Brightness / Contrast.
5. Layer -> New Adjustment Layer -> Photo Filter, Sepia, 100%.
6. Select your base layer. apply Sharpen filter, Filter -> Sharpen -> Sharpen
7. Edit -> Fade Sharpen, Overlay, 70%.
8. Now we should change sky behind the door.
9. Choose Polygonal Lasso Tool.
10. Make a new layer and make a selection like this:
11. To make it more precise you can zoom a little bit. While you're using selection tool you can press and hold Space to move your "Camera".
12. Choose base layer and Magic Wand Tool. Hold Shift to "Add selection" and click on the "holes" in chair. Remember not to deselect previous selection!.
13. Select our new layer and fill it with some color, for example dark red. (Shift -> Backspace).
14. Let's add something cool. Maybe dark clouds?
15. Nice image with clouds and thunder.
16. Copy, paste it under our Sepia layer and above rest. Move it like in a picture below:
17. Hold Ctrl and click on the thumbnail of "Dark-Red" layer to make a selection.
18. Select "Clouds" layer and click, Select -> Select Inverse, then Delete.
19. Spend some time to correct holes in the chair. Use Eyedropper Tool and basic brushes to paint.
20. Select your clouds layer, then Image -> Adjustments -> Brightness / Contrast and set -45/45.
Note: If you want realistic image you should spend more time to adjust shadows on the floor
21. Let's add some "dark" poster! (;
22. Find one -> Google Results for "Reaper"
23. Paste it and move like in the picture below:
24. Reduce poster's opacity and select Polygonal Lasso Tool and make a selection like this:
25. Set opacity to about 90% and set layer's mode to Luminosity (Experiment with other blending styles).
26. Now play with light. Select your base layer and choose Filter -> Render -> Lightning Effects.
27. Choose Flashlight and place it near the lamp.
28. Now you know some techniques, add more details ;)
More Tutorials: 
