Draw the design you intend to make onto a piece of flexible vinyl and cut out the portions that will be painted with box cutters.
Tape the vinyl template in place on the vehicle.
Choose which color you are going to paint with first. Start with background colors and darker colors, then work into the foreground colors.
Cover anything that shouldn't be painted in the color you just chose with masking tape. If you need to cover a large area, use the masking tape to secure sheets of paper or scrap vinyl.
Airbrush the first layer on to your car. You will use one finger to regulate the flow of air and paint with a lever that is usually mounted on the top of the airbrush. Remember that the closer you hold the airbrush to the car, the smaller a surface will be covered and your color effect will be more dense.
Remove the extra covering tape once you have finished working with the first color. Select your second color and cover any portions of the art that aren't to receive that color. If you're going to paint over the first layer, let it dry first.
Continue painting, a color at a time, until your design is complete. Wait until the paint is dry before you remove the main vinyl template. This helps prevent smearing.