Sections at a time because it settles to the lowest point. Slush a section and let it settle and cure in that spot, then rotate the armor piece and hit another section. Use a respirator and gloves. The odor is very strong. It can stink up the house quick so ventilation is a good idea. I use in my basement with the sliding door openAwesome. So if I had a peice that was done, should i do it in little small sections or just slushcast the whole peice at once