Dents, holes, cracks and nail-pops in drywall are common repairs. Drywall is softer and easier to damage than old-style plaster walls. A poorly done repair looks sloppy and lumpy, but it's not difficult to do it right. There are easy techniques and you just need some basic tools.
Fixing dents, nail pops and small holes
I find spackling compound easier for small repairs. It generally requires just one application, unlike joint compound.
For nail pops, gently hammer the nail back down so you have a dimple. Remove any little chunks of drywall and dust. This same technique can be used for molly or toggle bolts anchored into the drywall. Do not try to pull them out; you'll create a much bigger hole. Simply tap it down until it's a little below the surface.
Even for small holes, it is better to apply the patching compound an inch or two around the hole itself for a smoother repair. Use a 2" or 3" flexible putty knife.
Sand it smooth, using a light touch. Sanding sponges are ideal. If you use regular sandpaper, try to keep it flat while you sand. Wrapping it around a small piece of scrap wood or using a sanding block will help.
All patches need to be primed before you apply a final coat of paint. No need to use regular primer if you don't have any on hand--use a little of the wall paint for a first coat.
Repairing large holes
For bigger holes, the easiest solution is to use a metal mesh drywall patch, available at any paint or hardware store. They are adhesive on one side. Simply apply it carefully over the hole and finish with drywall compound. These patches come in sizes as large as 12" in diameter. Allowing for a few extra inches to ensure good adhesion around the edges, you can repair quite large holes.
You will need to use drywall compound instead of spackle for these larger repairs, and it will take two or three coats. Remember to apply the compound well beyond the repair itself so you can feather out the edges for a smooth finish.
If the crack is a persistent or wide crack in your drywall, you will want to use fiberglass tape under the drywall compound.
Using the edge of a putty knife, scrape loose material out of the crack.
Apply a coat of joint compound, forcing it well into the crack. Immediately put a piece of the tape over it, making sure it is well-embedded in the compound. Let this dry, and apply one or two additional coats of joint compiound until it's level enough to sand smooth.
For smaller, less persistent cracks, there is no need for tape, but be sure to clean any loose material out before starting the repair. I have found that forcing a bead of flexible caulking into a small crack before patching keeps it from reappearing.
If there is a texture on the wall, it is usually easy to replicate it. Some textures can be purchased in spray cans; check with your hardware or paint store.
Unless you are repainting the entire wall, the texture of the paint must also match. Hopefully you have some of the original wall paint saved. Rather than using a brush to cover your repair, use a small roller. Feather the paint out beyond the repair itself and it should dry to match perfectly.
Holes and other damage to drywall might seem like the end of the world, or at least the occasion for a call to a contractor. But with a little elbow grease and the right supplies, a dedicated homeowner can fix anything from a nail pop to a large drywall crack.
If you've decided to hire a drywall contractor, make sure you know the scope of the job and your budget before you hire someone.