Before applying spackle, you must clean and otherwise smooth out the area around the hole or crack so that the surface is optimized for proper spackling paste adhesion. Often, a hole in drywall, whether it’s caused by blunt force or by a screw, nail or other type of fastener, will have an outer edge or fragments that protrude outward. You want the area directly around the hole to be as smooth and even as the rest of the wall’s surface. Use a putty knife to gently scrape away loose paint and protruding fragments of wallboard until the surface around the hole is as smooth as the rest of the wall. Be careful not to make the hole or crack bigger. You’ll undoubtedly remove some paint sitting right around the hole, but since you’ll be painting over the spackling compound once it’s dried, don’t sweat it. Press the putty knife firmly against the wall at an angle and scrape up and down until the dust and debris stops falling.
Fine-grit sandpaper is good for smoothing down the surface around a hole if there are not too many fragments or a protruding outer edge. Just give it a couple of quick brushes with the sandpaper to smooth it down.
If you’re going to spackle over nails or screws that popped through your wall’s paint, use a nailset and hammer to push them in below the wall’s surface.
If you’re working on holes of 2" or greater in diameter, you may need to purchase or make a wall-repair patch and apply it before using joint compound to seal it in place. See Patch and Repaint Walls.
After you have scraped or sanded the area, wipe it down with a damp cloth to remove any dust and residue.