Step 4
Add a new layer, change the mode to Overlay 100%, and fill with 50% gray. Use the Burn Tool to darken the rocks more.
4. How to Add the Bird
Step 1
Isolate the bird from the background and add it to the upper middle section. Use the Free Transform Tool (Control-T) to make it much smaller to create an impression of distance.
Step 2
Create a Hue/Saturation adjustment layer to desaturate the bird.
Step 3
Use a Curves adjustment layer to reduce the bird's visibility, making it fade out into the foggy background.
5. How to Retouch the Arch
Step 1
Cut out the arch from the original image and place it above the stairs. Use a layer mask to erase the bottom and blend it with the existing ground.