1) Use a peel-and-stick patch to cover doorknob holes. The patch is an aluminum screen covered by fiberglass mesh. Peel off its backing and press the patch in place.
2) Use a 4- or 6-in. drywall knife to apply drywall compound over the mesh. Apply three covering coats in all.
1) Begin a repair to a severely damaged outside corner by cutting away the metal corner bead with a hacksaw.
2) Use a nail bar to pry off the damaged section of the corner bead. Hold the new corner bead in place and mark its length.
3) Cut the new section of corner bead to length and attach it with nails. If the surrounding paint is glossy, sand it before proceeding to the next step.
4) Finish the repair with several coats of drywall compound. The last coats are applied with an 8-in. taping knife.