All in all, I think there are a few important facts to note about washing cars, at least from what I've learned over the last few years. Also keep in mind, I am not an ultra anal-retentive personality type when it comes to detailing, but I like them to be clean and I like to know that (if im gonne put the effort into cleaning them and keeping them up) that I at least am doing it what I figure is the "right" way.
1. The best way to wash a car depends on how dirty it is. There's a big difference between what should be done to a car that needs dust and fingerprints removed vs. a car that has been driven for 3 days after 3 inches of snow in the midwest..
2. Good quality, clean microfibres are a must. When wiping a car down and a towel gets a little dirty (as in you can see any accumulation on the towel), just throw it in the wash pile and get a fresh one. A dirty towel will render every other point here useless...after all, this is the thing which you are rubbing directly on your paint.
3. A good lubricant (quick detailer, Wolfgang Uber or similar product) is a must when wiping a car down.
4. A good PH neutral (or close) soap is nice to have.
5. I've always found that spray wax is good for a number of things. Extra coat of protection, water beading, extending amount of times between washes, building up a protective layer for your paint from contaminants, and help in drying a car are some but not all of the benefits.
6. Since I started using coatings a few years ago, I've come to know the benefits. Some are hesitant to use a coating (as I was back then) but they really make cleaning and protecting any car a much easier task. Im personally not a big fan of clear bras (at least on the old cars) but i think a coating is a great addition to any Shelby Mustang's paint finish.
Anyway, some more of my thoughts. Have greatly enjoyed reading some of the other posters' thoughts.
Kind regards,
Vern