Washing a car is simple.. but improper washing can lead to damaging the finish. The reason we wash cars the way we do is to make sure we don't introduce any new swirl marks, marring, or scratches. The paint surface is very delicate.. anything we do, when we touch a car, could damage the paint. All the steps we follow reduce the risk of doing any harm to the paint. You also must be aware of certain things that will not come off in the normal process of washing a car such as tar, sap, iron particles, and built-up brake dust. All these things are going to take additional time, chemicals, and different processes to remove safely.
Step 1: Rinse the vehicle.
This may be obvious but we want to rinse off the vehicle, including the wheels and wheel wells, to remove all the salt, dirt, or anything that could get trapped in your wash mitt that might scratch the paint. Ideally, you want to use a pressure wash that has good FLOW aka gallons per minute, and not so much pressure, anywhere from a foot or more away from the vehicle. Be aware of any sensitive areas on the vehicle such as damaged areas, convertible tops, etc. We do not want to damage anything.
Step 2: The wheels.
We use a bucket specifically for the wheels for convenience to make sure we do not contaminate our wash mitts with any brake dust, dirt, old tireshine, etc. but you can just also just make sure to clean out the bucket after if you plan on using it to wash the rest of the car. There are a variety of brushes and chemicals available to use to clean wheels and tires. We use a high-quality dedicated wheel and tire cleaner but a properly diluted degreaser will do the job. Coat the wheels and tires with your cleaner and agitate with your brushes, wheel mitt, or microfiber towel. Make sure to rinse and not allow the cleaner to dry.
Step 3: Two-bucket wash
Take one bucket, fill it with water, and use a "grit guard or dirt trap" if you can to prevent picking up any dirt that gets in the bucket. This will be your rinse bucket and will be the first stop for your filthy wash mitt after you pull it off the car.
Fill a second bucket, use another dirt trap, and the recommended amount of your favorite car soap (DO NOT USE DISH SOAP). This will be your Wash Bucket, which is the second stop for your wash mitt. Activate the suds by spraying high-pressure water into the bucket.
Dip the wash mitt into soapy water and wipe the vehicle from top to bottom in straight lines, one panel at a time. After each panel, remove it from the paintwork, rinse it in the water bucket then back into the soap bucket. Repeat the process panel by panel until the entire car is clean, then rinse the car thoroughly from top to bottom.
Step 4: Drying
Dry the car starting with the roof and windows with a clean microfiber or drying towel with little to no pressure. If you have an electric blower handy you can use it to blow off the majority of the water before using towels. A drying aid or "spray detailer" is also helpful to prevent any water spots from being left behind and add a little protection to the vehicle. Dry the wheels and door jambs with a separate towel to prevent cross-contamination with the paint. A properly maintained car will be hydrophobic. If you notice the water does not bead up on the paint it is time for a wax or another type of paint coating.
That's all it takes to safely wash your vehicle. It is pretty simple when you have the right tools and the right process.