I´m a Meguiar´s Products fan, I have almost all of their non-professional car care products.
I´m attaching a general interest letter I received from Meguiar´s in reply of a long question that may help us in some of our most frequent doubts. Hope it helps.
Thanks for your interest in Meguiar's. I hope you found the website helpful
The Clay bar will remove anything above the surface and make it as smooth as
glass. You should use this right after washing the car. Here is the best
way to use the clay:
First, tear the clay in half and make a pancake out of half of the bar.
Next, lubricate a 3' by 3' area of your vehicle with the Quik Detailer.
Also, lubricate both sides of the pancake you just made. That way the clay
will not stick to your hands or the vehicle. Then, glide the clay lightly
over the surface in a back and forth motion. Do not apply a lot of pressure,
just let the clay glide. After you make a couple of passes in that manner,
wipe off the area with a towel, ball up the clay and make a fresh pancake
out of it then move to the next area and repeat the process.
I would recommend that you try Meguiar's Scratch X on a small section of the
car when you want to clean up the finish. You would use this after the Clay
Detailer. Work the product into the area with a foam applicator pad or 100%
Cotton Terry Cloth Towel and wipe off product before it dries. You should
follow this product with a polish and a wax.
If two or three applications of Scratch X don't remove the spots from the
surface of you car, you will probably need to see a professional detailer
for a paint evaluation.
We recommend polishing and waxing once every two to three months. This will
help keep a show car shine.
The Gold Class Wax is our highest glossing wax. It will polish and wax in
one step. The Medallion is our best protecting wax. It will give you the
longest lasting protection. Either one would work great on your car.
Hope this info helps.
Meguiar's Surface Care Specialist