Wash the car and work in a shaded cool area. Wear gloves. Apply a small amount of the chemical to a towel and rub the surface in a circular motion until the water spots disappear.
Step 2. Neutralize the Acid
The Removing chemical has acid, so you'll want to neutralize the acid with soapy water or detailer's spray every 10 minutes.
Step 3. Removing Water Spots from Glass
Water spots on glass often require that the chemical be applied to very fine steel wool, then the glass be rubbed with medium pressure to remove the water spots. Do not use steel wool on mirrors. Use the chemical and a cloth only.