If you do create your own stencils for airbrushing your automobile do not use paper to create your stencils. Automobiles need lots of paint and this will damage paper stencils rather quickly. So stick with plastic or vinyl material for your stencils. A great cheap plastic to use for stencils is thin plastic folders. These can be picked up cheaply in office supply areas of most stores.
When doing airbrush art there are different types of airbrushes that are available. The best airbrush to use for putting airbrush art onto an automobile is a gravity fed airbrush. This is the one that professionals use and will give your artwork a high quality look. The paint can be automotive paint but make sure that you use a well ventilated area as the fumes can pose a health hazard. It is best when using automotive paint to wear a respirator at all times. When using automotive paint make sure that it is thin enough to flow through the airbrush. If the automotive paint that you have chosen does not flow then thin it down so that it flows. The paint should be thinned to about a milk thickness. A good automotive lacquer will work fine to thin down your automotive paint.
Different airbrush art calls for different psi on your compressor. PSI stands for pounds per square inch and for automotive airbrush art you need a compressor that has a psi of 55-65. Iwata is a great name brand to go with and they offer four compressors that will work for airbrushing automotives. Badger is another good name brand that you can go with. They offer several air compressors that will work when doing airbrush art on automobiles.
When it comes to any part of your actual airbrush equipment such as the airbrush and its parts as well as the compressor make sure to go with name brand. Do not use any knock offs a these will cost you more money and lots of headaches in the long run. You get what you pay for and when it comes to airbrush art you need to go with names that you can trust. A lot of knock offs also will give for a harder time finding replacement parts when they tear up. Knock offs will tear up quicker than the name brands. So save yourself the hassle of being in the middle of your airbrush art project on your automobile and find yourself unable to get replacement parts for your airbrush equipment.