The mountains in here are simple; I just used the same colour as the ground, and first blocked them in. Certain shapes don't all have to be the same but just mix it up a little bit. As the mountains go further into the background, they drop in saturation, so remember that. Once I have my mountains blocked in, you'll have to highlight them from the sun beams, which will just be a lighter brown or so forth. Use a size 4 brushes, pen pressured, to scribble some light source on them.
Next, you're going to be starting to smooth out the colours some more, bring down the hard shapes and just blending them over the other clouds. To do this, I used a soft brush again, and turned it on Flow. While lowering the Opacity to the slightest of 10%, you can really start to blend those hard edges in with the soft ones within a few strokes. We're also going to use this step on the bottom, underneath the clouds. Mostly that giant dark blue blob across the bottom layer. In step 9 they look way too hard to be in the sky, so we need to patch those up, by again going over in strokes. As you can see, I've also gone and shaped the bottom mountains again, just keeping them formed and not thrown in there. I've also gone ahead and added some more negative space to the clouds on the right side and at the top, so they don't hog up the entire picture.
Now you might be thinking, 'whoa where did that bottom come from?' Well I decided to open the picture more, so it's not so one sided, and I obviously took some inspiration from the Route 66 drive. So by doing that, I cropped a larger half at the bottom into the picture, and then used a hard brush to fill in my colours. To extend the perspective, I added some phone line towers down the road; it gives it a longer feel. In the clouds I wanted to add some bloom to the cloud. By doing so I use a soft brush set to screen, and pick a pretty pale blue to fill in those negative space spots in the clouds, as if the sky is pushing itself through. Also the main focal point, the white, I blotched in some other colours because the white felt too strong to me.
Now for the road texture, I created a dark brown texture on a new layer that would fit inside the road space, and then set it to the Filter/Texture/Grain. After I had the right texture I wanted, I then set it to Overlay over the pavement. I then painted two white lines down the road, ass well as the yellow follow lines in the middle. Using a brush on Overlay, I created some glare off the sun onto the road. Once you're finished with that, merge all layers together.
For the final step, I wanted to fill in that ground on the left and right with just something simple. So I used the Grass brush something I would never use on anything else, but it did work here. Also by setting two beige colours to it, I started to fill in my grass/weeds around the area. Then I used the dodge tool, on a soft brush and started to highlight the pavement some more.
Then you can use a three sized brush, and create some oil stains on the ground, or use a light colour and create some more glimmered speckles of the ground or rubble. And that's it for this tutorial!