Keeping your car clean is a major role of keeping it running. There are several methods that you can use to clean your car. The safest, quickest, and most effective way I find to clean the car is compressed air. For bigger messes you could disassemble the car and clean the parts individually with denatured alcohol.
Cleaning formulas are also used. You can use simple green and a tooth brush to get grime off your chassis and other parts. The tooth brush can be a very effective tool for cleaning. For cleaning tires while mounted on rims you can plug the holes on the inside of the rim, then rinse them under the sink and scrub with a tooth brush. When racing or bashing for long periods of time it is important to keep your tread showing, not what they run on!