One way to soundproof your home is by adding soundproof panels. These panels are specially made to go under the drywall and over a backing of fiberglass insulation. If you have drywall already up, you need to remove it before beginning the project. Or if you don't want to remove the existing drywall and install the panels over it, skip Step 1. You will not need fiberglass insulation. Measure the height of the wall and break it up into 16-inch increments. That will tell you how many strips of resilient channels you will need.
Get Ready to Install Fiberglass
Be really sure to wear protective clothing, gloves, and eyewear during this step to avoid very uncomfortable itching or possible eye injuries. Unroll the fiberglass and push it into the openings between the studs. Push it in firmly so it stays.
Install the Resilient Channels
Resilient channels are strips that are put over the fiberglass that allows walls to push in and out with sound and not have an empty chamber to cause the sound to carry. It will not bounce off the walls and therefore be absorbed into the walls. Install the strips horizontally across the walls every 16 inches with the movable sections pointing up.
Install the Soundproof Panel
Measure your soundproofing panels and using your utility knife cut to fit. Install them Foil side out, over the fiberglass and resilient channels, and secure them using the drywall screws. Make sure that the drywall screw doesn't go in far enough to tear the foil covering over the panels. Make sure to secure them with at least three or four screws on each side.
Seal the Panels
Now you are going to use the tape you bought to seal the panels where they meet vertically. Make sure to carry the tap all the way to the top even and the bottom even. Now use the acoustical sealant and seal around the top and bottoms of the wall. This is an extra measure that will pay off in that there are no holes for sound to leak out or in.
Install the Drywall
Now you are going to measure the walls and the drywall. Use your utility knife to make any cuts that need to be made and snap it in two. Place the drywall panels up over the soundproof panels marking where the screws are in the panels so you can stagger the panels, putting them where the edge of the soundproof panel is not. If necessary, use longer drywall screws to attach the panels through all the walls to secure them tightly. Make sure you have the screws in tightly. You are now ready to either paint or texturize your wall.