A game while waiting
It's allways very usefull to carry a Game Boy in your X-Wing.
Complete Tutorial
https://www.3dtotal.com/tutorial/2472-making-of-a-game-while-waiting-3ds-max-photoshop-by-lvaro-calvo-escudero-star-wars-x-wing-3dsmax
Take a moment to think, let yourself go, then draw and redraw until the next step.
Having a solid composition with correct perspective is a useful basis to start your image the right way.
Start painting light and shadow to get a base with the desired color temperature.
Build your own texture library. There are a lot of free sites for this, but always travel with your camera too.
Redefining parts and starting deep on details.
Our player is here. We really don't need so much detail, but he's still the focal point.
Before this step I like to take one day as a break if I can, and come back with a fresh mind!
The work is complete, but you can use some common tricks to unify the elements.