Mud over what you taped and let set. Note: float tape and feather in outside edges, let set well, then scrape any high spots flat, then recoat. Depending on your skill at this, you may need to skim (lightly coat and sand) the entire wall. I have wall, part of which is high quality birch plywood, the other part is half inch drywall. Im going to use wood filler to the holes over the joints of the plywood. However, i have the drywall-birch plywood boundary to contend with. if i use drywall mud to cover the boundary will the drywall mud stick to the birch plywood? When you get to a seam between two pieces of drywall, apply mud to the crack and then tear off a piece of paper tape the length of the seam. Press it lightly into the mud and over the seam. Now put another coat of mud over the paper with your 10 or 12-inch knife. Repeat this process until the entire wall is covered. Your paint job starts with cleaning the surfaces to be painted, probably walls or a ceiling. It's not a sexy job, but every wall and ceiling has plenty of dust, cobwebs and other dirt particles on it, even if they're not visible, and you don't want to be painting over them. The drywall in kitchens ... This paint coating evens out the porosity and texture of the drywall so the finished paint looks superb. After you have third coated and finally sanded the seams, corners, and nails, you MUST apply a superb sealer/primer to the walls before you paint. Step 2. Smooth seam tape over the layer of mud on the joints. Press it down with a drywall knife to remove air bubbles. If you're using adhesive tape, wet the tape and apply it to the joint. Make sure the tape is perfectly smooth.