simply stated; you have 2 buckets; 1 for clean water for rinsing and the other bucket for the shampoo. Wash each panel with a loaded chenille mitt, or whatever you prefer and after each panel, rinse the aforementioned washing tool, dislodging any dirt/grime, etc from the mitt minimizing scratches, swirls. Also be sure to use linear motions when washing, bumper to bumper mimicking the way air travels over the car, minimizing swirl makrs.