Slice each foam square in half to create a wedge shape.
Lay the first board on a flat surface -- the floor is fine.
Mark out mounting holes for the hinges. Position the top hinge approximately 24 inches from the top of the board and the second hinge 24 inches from the base.
Glue the foam squares to one side of the board, leaving a space where the hinge mounting holes are plotted. You do not need to cover the entire surface of the board if you have sufficient foam material. The purpose of using the foam wedges is to create an irregular, peaked surface on the inside of the booth. This peaked surface reduces sound reflections and “dampens” the sound of the drums when they are played inside the booth. This makes for a slightly quieter and more controllable sound for recording.
Lay the second board next to the first and mark out hinge mounting holes so they are exactly level with those on the first board.
Cover the second board with foam wedges.
Bore the mounting holes using an electric drill and 1/8-inch drill bit.
Flip the boards over so they are foam-side down. Line them up so the hinge mounting holes are level.
Place the hinge over the mounting holes so the screw holes in the hinge line up with the mounting holes. Screw the hinge into the back of the first board, then screw the other half of the hinge into the second board.
Fit the second hinge in the same fashion. Repeat this process with the remaining two boards, so you have two pairs of connected board, each covered in foam wedges.
Set up the drum kit in the center of the room, leaving sufficient space around the kit to erect the boards.
Fold the first board toward the second board so the two boards are at a 90-degree angle.
Lift the folded board up by about 4 inches, so you can slide your hand under the flat board. Carefully lift the two boards up and if necessary, adjust the angle of the boards if they moved when you were lifting them. Because the boards are hinged together, standing them at a 90-angle is sufficient to ensure they do not fall over.
Lift up the second pair of hinged boards and position them so they face one another, forming an open-top enclosure.
Maneuver the boards so they surround the kit. Leave a gap so the drummer can get in.
Drape a sheet over the top of the enclosure and tape it to the outsides of the board.