You should never wash your car in open sunlight if possible. Also make sure the car is cool. Wash water and rinse water evaporate too quickly and tend to leave water spots which are salt and mineral deposits. Such deposits are capable of eating through wax and etching paint if left on the painted surface for any length of time. Use lukewarm or cool water. Water which is too hot or too cold can cause a shock to the paint and lead to microscopic fractures of the paint surface.

Never use household detergent --powdered or liquid-- these soaps are formulated to scour metals, plastics and porcelains to remove grease and oil. The mere fact that soap is advertised as being gentle to your hands does not mean it is gentle to your paint/wax finish. Many of these soaps have high sodium or alkaline content and are too strong for automotive care. These soaps can accelerate paint oxidation by depleting the oils from the paint and also removing existing wax. Use a pH balanced or neutral (pH7) soap on your car. Always check the label of the soap you are using for a listing of all the ingredients. You are better off using too little soap than too much. Too much soap will leave a residue if not rinsed off thoroughly.

Wash the car from the top down. Some detailers use different sponges or mitts for the upper part of the car from the lower part of the car, since there are more dirt particles on the lower part of a vehicle closer to the road. Rinse the car often during the washing process. Use a large bucket like an old 5 gallon joint compound bucket or a plastic bucket from your favorite local donut shop.

Adding a teaspoon of vegetable oil to the bucket prior to adding water and soap will assist the soap in carrying away the dirt particles from the painted surface during the washing process.

In drying your car, use at least a couple of towels; one to quickly push the water off the car, the other to dry the surface of the car. Open up all doors and lids on the vehicle to enable semi exposed areas to dry completely. If you insist on a chamois, use only an English Cod Oil tanned chamois. Other chamois may remove wax and eventually scratch the paint surface. Synthetic silicone-free chamois are available for quick and easy water removal from the car. In any event, the final drying procedure should be done with a cotton tow