 wax
If your paint is in really good shape but you have some tuff water spots, this is a fix.. (disclaimer.. it worked great on mine anyway)
Wash the car in Dawn or something equiv. If it takes grease off of dishes, it will take wax off of the paint. You need a good base to work with.
Use a clay bar, make sure to follow the directions. Its kind of like wet sanding in a way.
Or you can use a light cleaner like Meq. #3. Go side to side , NEVER in circles
I use the Meq. #9 to even it all out then finish with a good wax like the Meq. #26.
There are several good waxes, just find one you like. I used the above combo for years on a black GT I had.
Take your time and make it shine! | 
