Drywall finishing is the process of covering up all of your joints, screw and/or nail heads and any breaks or cracks that may have occurred in the drywall. Hanging the drywall is the step that gives bulk to the walls, but it's the finishing that completes them. From there they are textured, coated in primer and painted. Only when properly finished is a drywall completely free of gaps and noticeable texture. When doing the hanging and finishing yourself, you will likely spend most of your time on the finishing. It's worth it, though, in order to create smooth and beautifully finished walls.
What You Will Need
Finishing your hung drywall starts with having the right tools and materials. Drywall tape and compound are the two required ingredients. Most non-professionals use all purpose drying compound, because it doesn't harden too quickly and can be used for all finish layers. Sheetrock brand compound is the easiest to work with. The tools you will need include 3 different sized drywall knives, utility knife and a drywall trowel.
Finishing: The First Pass
In all, you will apply 3 coats of drywall compound over each joint. On the first pass, your task is to properly adhere the drywall tape over the joint. Fill up the drywall trough with all purpose compound. It comes premixed and is ready to apply. Much like putty, cover the smallest of the drywall knives with compound and smear mud over the entire joint in a smooth motion. Once the joint is filled, stick the right length of drywall tape over it. From the top down or from one side to the other, run the knife over the tape, pressing it further into the mud while at the same time squeezing out excess mud. Go back over it once more to wipe away the excess mud.
The Second Layer
Once dry (it can take up to 24 hours), go over each joint again with another coat of mud. Use the second biggest drywall knife this time. Your goal with this layer is to fully conceal the tape. The wider knife fans out the mud farther from each side, slightly reducing the taper of the tape and mud. Scrape away the excess once again. Do this for every joint. This will have to dry as well. In the meantime, take a knife and mud over every single nail or screw head on the drywall. One coat will suffice, just make sure it's as smooth as the wall.
The Third Layer
The third layer is the finish layer. Using the biggest drywall knife you have, go over each joint a third time, fanning the drywall compound out even farther. You may be left with a 10-inch swath of mud over each joint. This helps to spread out the coating and make the wall as smooth as it needs to be.
Drywall finishing involves the application of 3 layers of drywall compound. Each layer must be allowed to dry before the next can be applied. In addition to the joints, every indentation caused by nail or screw heads or breaks needs to be smoothly covered with mud before the primer and paint can be applied.