| Two bucket method is worth doing. What I do is have one bucket filled with clean water, the other with a warm shampoo solution (I use either Autoglym or the Zymol one you can buy in Halfords).
I use a microfibre wash mit. Rinse the wash mit in the clean water, then into the shampoo solution. After every time it has been on the car rinse it off in the clear water etc. etc. This hopefully removes any trapped dirst/grit which could lightly scratch the paint.
I do roof, bonnet, sides, hatch & rear bumper, front bumper, sills/wheel arches, wheels in that order.
To clean the wheels, I use a pan scourer for NON-STICK pans. One with a white scouring bit - this does not scratch the wheels.
I dry with a large, soft micro-fibre towel. The water here is soft so spots are not a big problem.
To protect the paint, I use Klasse All-in-one, topped with P21S wax. If you want a one step product, something like Meguiars NXT or Gold Class wax are fine. Avoid Autoglym are they are terrible for staining all the black trim.
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