picked up a clay bar, how does it work

I wouldnt use anything but your hands...keep the orbital polishers put away. It can cause a hell of a mess. Streaks, swirls, burn spots...All potential problems. especially on new clear coats...Wash it with dawn, lots if rinse water, dry it good, clay bar it with LOTS of detailer spray, use back and forth action (north-south) not circular, do it in small sections, like 12-10 inches, wipe each section dry then go on to the next. Lots of fold and refold on the clay. Watch out for hidden grit. Clay bars bring up all kinds of awful crap you wouldnt believe was inbedded in your paint. After your done, give it a wash with somthing good like Mothers or even turtle wax. Then go to work on the polish with somthing light. I use mothers Reflections. Its the best stuff out there and I've used them all on a black car...the worst color there is to try and get right.. Let it sit overnite then repeat the polish process again. Yeah it eats up a weekend but its worth it and you'll WILL love the way it turns out. Just skip the electric stuff. You stand too much of a chance of f***ing it up...(take it from me)...
 
They are using the Dawn to get all of the wax off of the car. They are reapplying wax afterwards. They aren't using Dawn to wash their car everytime they wash it... At least I hope not.

I myself am too much of a paint coward to use Dawn on my car, I just stick to the Mothers car wash and wax. My car looks and feels good to the touch when I am done. I know it isn't as good as claying the car and polishing etc.. But I would rather be out driving the car on a nice weekend day than speding the 10 hours needed to clay and polish and what not.... As soon as you take it out on the road the car gets dirty anyway (you know that rubber that cakes on the rear fenders hehehe)..
 
Regarding Dawn or any other dish soap: It should only be used to remove the old wax from your car prior to applying new wax. It should not be used every time you wash your car. The obvious reason - it strips wax (dish soaps are created to remove grease, they will also remove wax).

When you are just washing your car you should use a car wash specific soap. They will not strip the wax from your car.