How often should I treat the car with the yellow Supagard polish?
That’s a bit like saying, “How often should I clean my house”. As with most car care products, you should use them when the car needs it. Some people never use the cream at all, instead just using a wash-&-wax when they wash the car. But if it was me, I’d do it maybe once a year, and then washing my car I’d use it to do any lightly scratched areas, for example around the door handles and on the leading edge of the bonnet, essentially using it as a polish and scratch remover/hider.
