Score drywall to the size of the wall you plan to soundproof using a utility knife. Bend the drywall at the scored marks to snap the cut pieces free.
Apply Green Glue to the interior surface of the drywall using a caulking gun. Use an applicator tube when applying five-gallon pails of Green Glue.
Fit the drywall into place with screws, driven into the wall studs approximately every 12 inches, using a power drill and driver bit. Allow for a few weeks, or up to 90 days, for the Green Glue to expand fully between the drywall and reach its maximum sound blocking potential. Use this same technique on ceilings as well as walls.
Cut a piece of mass-loaded vinyl and a matching piece of open-cell polyurethane the size of an area rug or carpet, using a utility knife.
Lay the polyurethane foam on the floor where you wish to lay the area rug or carpet.
Lay the mass-loaded vinyl on top of the polyurethane foam.
Lay the area rug or carpet on top of the mass-loaded vinyl. This method can greatly decrease the amount of noise that reaches neighbors on lower floors.
Cut a sheet of soundproof foam into the desired lengths.
Tape the cut lengths of soundproof foam in the desired position on the wall using masking tape.
Screw the soundproof foam into the wall with screws, using a power drill and driver bit. Soundproof foam does not entirely block sound, but it does dampen echo and reverberation, elements that may contribute to increased noise.