Measure the room and decide how large you want the wall panels to be. Decide whether to purchase frames in this size or build frames from wood. Acoustic materials stores sell frames for making acoustic panels, and very sturdy and somewhat thick picture frames also work.
Purchase or cut 2-by-4s in the right sizes to build frames for the panels, if you decide to build frames yourself.
Build frames for the panels. The simplest way to build frames is to screw 2-by-4s together into rectangular or square shapes.
Attach a sturdy backing to the frames, such as a sheet of plywood cut to the same size as the frames.
Fill the frames with foam or insulation. You can use standard wall insulation, special acoustic insulation, specialized acoustic foam, or materials from around the house, such as foam packaging for fragile items or memory foam.
Cut fabric rectangles large enough to cover the foam or insulation and fold over and around the panel frames. Choose a fabric that matches the decor of the room. For a home theater, many people prefer dark-colored fabric so the panels do not distract viewers from the theater screen.
Cover the frames with fabric, folding the fabric around the frames. Secure the fabric to the back of the frames with staples.
Attach hooks to the top of the frames to make it possible to hang them from the ceiling, or attach brackets to the frames to hang them from the walls of the room.