Mark the desired location for the AC vent on the outside of the vocal booth with a marker. The vent should be placed in the upper area of the vocal booth, because cold air sinks and the cold air can filter down through the booth. Make sure the stream of air from the vent will not blow directly on the vocalist or microphone.
Draw a circle 6 inches in diameter around the center point of the marked location for the AC vent with a compass. Any size vent may be used, but a smaller vent will let in less outside sound.
Put on safety glasses.
Drill a hole at the center of the circle with a power drill and a large drill bit.
Cut out the circle from the vocal booth with a sawzall, starting in the drilled hole and working your way around the circle.
Screw a 6-inch duct plate over the hole in the vocal booth with a power drill and driver bit.
Secure the rectangular end of a 6-inch round duct horizontal adapter to the cold air output of a portable air conditioner with duct tape.
Secure one end of a length of 6-inch-wide insulated flex ducting to the round end of the 6-inch round duct horizontal adapter with duct tape.
Secure the opposite end of the flex ducting to the duct place with duct tape.
Mark the desired location of the portable AC unit's exhaust on an outer wall with a marker. Ensure the hole is between wall studs and away from any electrical wiring in the wall. If a window is available, the exhaust duct may be placed in a window with the included window adapter.
Mark a circle the same diameter as the portable AC unit's exhaust duct around the marked position on the wall.
Drill a hole through the center of the marked circle on the outer wall with a power drill and a large drill bit.
Cut out the hole in the outer wall with a sawzall starting from the center hole and working your way around the circle.
Screw a duct plate the width of the portable AC unit's exhaust duct over the hole in the outer wall with a power drill and driver bit.
Secure the end of the portable AC unit's exhaust duct to the duct plate in the outer wall with duct tape.
Plug the portable AC unit's power cord into a power outlet.