Step 5: Priming
Painting, then, is important to do in a well-ventilated area. Before priming and coloring the frame, you need to prepare the wood so the paint will be smooth and even. The first step is to sand down any rough or uneven areas. Use something between 120-240 grit sandpaper. Next, fill in any holes, dents, pores and imperfections with wood filler. Use something like a credit card to apply wood filler to areas that need it. If you used natural wood instead of MDF, you should smear the whole thing with wood filler, to fill the crevices and pores present in all natural wood.
Let the filler dry for about 30 minutes and then gently sand the whole thing with 200 grit sandpaper. The next step is to prime the frame, which is a vital step for good painting. Use any brand of sandable primer. The best way to prime is to use many light coats. Quick sweeping motions will help ensure even coverage. Apply primer to one side, let it dry, flip the frame over and prime the other side. Wait at least 30 minutes before adding another coat.
