Non-Sanding just means you don't have to sand as long as you recoat within the recommended window. If there is a blemish, just let the sealer completely dry, then sand as necessary. You will have to re-seal before you paint. You should also finish sand with a bit finer grit paper at least 400-500 grit. Some people go as fine as 600. You should also get the P-sheets for the products you are using. These will tell you exactly what you can and can't do with the product.