This is one of the many viable methods there are, and is very friendly for beginners because it can provide extra safety by sparing you from washing the dirt out of the mitt during the wash. Depending on what kind of mitt you use it can come out a little more expensive vs. other methods and also you will have much more laundry to do after this.
First off let me start that a Pre wash still is essential and will make ANY wash much safer and easier, so if you are here you should have taken the concept of prewashing already to your heart.
What do you need?
- A bucket (can be any bucket, if you are somewhere where Gallon Buckets are expensive this can be a big money saver)
- Shampoo of your choice
- Multiples of your preferred wash media
- Water, only enough to get the mitts fully wetted
- Optional but very much recommended: A dirty towel bin bucket to collect dirty towels
How does it work?
You fill the bucket with water and add the correct amount of shampoo, then you drop the wash media inside. You take one out, start to wash top down without pressure.
Especially for beginners its recommended to control for dirt after each swipe. If you see dirt switch to a new side or new wash medium, if there are no more sides you put the used wash medium in you towel garbage bucket.
The control becomes even more important the more you get to the real dirty areas like the bottom part of the car.
What makes this safe?
Swirls mostly come from two things: excessive pressure while washing and also dirt rubbed against the paint. While a good mitt or towel provides some safety for this not eliminating any dirt you took off the equation can makes this method very safe.
How many Towels/mitts/… do I need?
A really hard question to answer, I would start out with at least two sides (a mitt has two sides, a towel has eight) per panel, potentially more for large panels (hood, roof). In the end this is down to a lot of factors, better to have a little too many than too little. I especially advice to have a small thin towel for those really hard to reach areas, maybe with a old credit card to make it go into those spots.
Something did not get clean by this?
Even a contact wash is not the final step every time. Some contaminations need more attention and a full on decon wash.