Hi, I did not sand. I did not paint any other paint. I decided to do that painting after the Kiwigrip. The deck had already lost all gloss and was very rough. I washed it first, but that's all. There were some spots that we had cut into the deck and repaired something. Using Kiwigrip over those areas was especially fitting since it covers and unifies irregularities to some degree. I used one coat. Adding a second coat would be somewhat difficult since you have paint peaks. I'm sure it can be done but I'd suggest doing a test area first to get a feel for it. I forgot to mention I did that test in an area where it was not important to have really good traction. You can roll and reroll until you get it to the aggressiveness that you want, until it dries, which it does quickly in sun.