In this tutorial i will show you the basics of adding graphics to your digital dream after that you left to your own apply your graphics.
First pick the car you wish to add you graphics to.
Either draw sum graphics or get them off goggle(where i got this image from).
Remove the background from the image and copy the image onto the canvas with your car.
Now size the image so it will fit onto your car in the required place and put in roughly where it should be.
Press ctrl+t to enter free transform mode, and the right click your image select distort from the menu.
Using the corner anchor point adjust your image so it looks in perspective with its location on the car.
Adjust the opacity and fill settings of the layer to make it blend in better
and that's the basics of adding images.
If you wish to add other images such banners just use
the same technique above and use the eraser tool on soft brush with low
fill and opacity settings and carefully remove the excess.
And you can have some thing like the image below
More Tutorials: 
