After you wash and dry the vehicle, the next step is a product called Iron Out by Auto Finesse. This also is a great product to use before claying. This makes claying a vehicle much easier. You can apply the product over the entire car (glass, trim, wheels, ect). As the product beings to work a purple residue will show all around the vehicle. When you rinse the vehicle you have to use a TON of water. If you think you rinsed it enough; keep going. LOL