Here is my fav pic I have taken.

Now I find exposure, contrast & grids are key to a good picture, also reducing the colour to 44/46.
Also depending on how you want you finial image to look, location is key to, I wanted the focus on the car but I also wanted a nice backdrop in the above image.
I usually set the aperture to 33, gives a nice blur but not destroying the background. I also don't have the car in full focus, I set the focus on the car at the middle & move the camera back untill it just blurs the rear, (you can use the focus slider, but I find I have more control doing it my way) I find in the game a slightly soft finish makes it look better.
Here is another example where the car isn't in full focus & it looks cracking.

In the end trial & error will prevail.