I use Rain X car wash, it says you won't need to dry it afterwards, but if you do you will find you can eliminate virtually all waterspots. The car has to be cool and in the shade. Then I just dry the spots off with a chamois. It spots up the windows quite a bit, but you probably wanted to clean those anyway. Tip: Shove a towel in the scoupe while it's drying, that way you don't get streeks of running water.