Walk into the vocal booth and close the door. Use measuring tape to measure the length and width of the doorstop on the inside of the door.
Lay out your sealant material on a flat work table. This should be a long piece of either weatherstripping or neoprene foam.
Transfer the measurements taken in Step One to the door sealant. Measure out two length measurements and two width measurements. Mark each measurement on the sealant using a carpenter's pencil or permanent marker.
Cut the strip of sealant with a utility knife or hack saw, depending on the material. Use the utility knife to cut holes in the sealant about six to 12 inches apart. These are for the screw holes as you mount the sealant on the door.
Place the lengthwise sealant strip firmly against the door. Make sure the top and bottom edges of the strip are flush with the top and bottom corners of the door. Use an electric drill and 1/4-inch drill bit to drill the pilot holes into the door stop through the pre-marked holes in the sealant.
Hold the sealant in place, attach a screwdriver bit to the drill and fasten the sealant to the door stop with several 1/4-inch screws.
Repeat the above procedure to install the second lengthwise sealant strip, and the two strips of width-wise sealant along the top and bottom sides of the door.