Next, apply a coat of drywall joint compound over the tape and screwheads using an 8-inch drywall knife. Allow the compound to dry overnight, then use the knife to scrape off any ridges or bumps. Apply a second coat of joint compound over the entire patch, only this time use an 8- or 10-inch drywall knife. When this coat dries, scrape off the high spots and apply a thin coat, feathering the edges over a wider area.
Wait overnight, then lightly sand the area with 150-grit abrasive sandpaper. If necessary, apply a final skim coat of joint compound to fill any small surface imperfections. Apply two coats of paint to the patched areas. If the newly painted sections stand out from the surrounding area, you might want to paint the entire wall.