The first time I waxed the roof, I used a auto paste wax on the entire roof.... smooth areas were no problem, the textured walkways were a real challenge to do. They ate up polishing rags like crazy. Since then ( 9 yrs ag), I've been using Optimum Spray Wax on the roof. Both on the smooth and textured areas. It have pretty good UV protection . Just spray it on and give it a quick wipe. Since it's so east to do, I do it 3 times a year.
Here's the product I use....
https://www.autopia-carcare.com/opti...E#.Ym_GBejMKM8