Never mind, I found the post from Zto5

 

I remove by hand. Might be able to use a machine but I think it'll build up too much heat.

Clay bar is step 1 after car is washed. Use a quick detailer and hose down the area to be coated, then run the clay bar over that area to remove stuck dirt and grime and whatever else. Don't have to press hard, be gentle. It'll run freely over the area when it's clean. Always keep a clean part of the bar on the paint, so once you do an area fold it over so a clean portion is available. After that you can Polish and wax and whatever else you want to do.