Gather materials: drywall patch, utility knife, drywall saw, joint tape, joint compound, putty knife, sandpaper, primer, paint
Cut away loose or damaged drywall around the hole
Trim the hole into a clean square or rectangle
Cut a drywall patch to fit the opening
For small holes, use a self-adhesive patch or spackle
For larger holes, install a backing board behind the hole
Screw the backing board into place if needed
Attach the drywall patch to the backing board or fit it into the opening
Apply joint tape over seams
Spread joint compound over the patch and tape
Let the compound dry completely
Apply additional thin coats of joint compound as needed
Sand the repaired area smooth
Wipe away dust
Apply primer to the patched area
Paint to match the wall