Typical cushioning fabric is thick felt you can purchase at any hobby shop. It is used to provide protection for high-end musical instruments, fine woodworking, jewelry, glass or any item that might be scratched or broken. Woodworkers apply it with a sticky spray-on glue known as trim cement. It is a straightforward procedure that doesn't involve cutting individual panels for every side. Trim cement will condense and compress loose corners, flaps, wrinkles or just about anywhere the felt gets stubborn and doesn't want to lie down.

Stretch out a tape measure. Bend it and place it inside the box so that the end of the tape is at the top and flush on one side, drops down to the bottom, runs across and up the other side. Measure the box in both directions. Add 2 inches to both measurements. For example, if the sides of the box were 12 inches tall, and 12 inches across the bottom, the measurement would be 36 inches. Add 2 inches for a total of 38 inches.

Cut a single piece of felt to the measurements with scissors. Use a straightedge to get the cuts straight. It will be either square or rectangular. Spray the inside of the box with trim cement. Give it a wet coat without any dry spaces.

Spread the felt out over the top of the box. Carefully bend and allow the felt to drop into the box. Maintain even spacing as the bottom of the felt contacts the bottom of the box.

Spread the felt along the bottom of the box with your fingers. It will instantly adhere to the bottom. Spread the felt up all four sides evenly, moving from side to side as you work your fingers up from the bottom.

Insert a stick into the corners. Slide the stick up the corners, pressing the felt tightly into the corners. Work out all the wrinkles with your fingers. If the felt bunches up slightly, use the stick to press down hard to compress it until the felt stays flat and the inside of the box is covered.

Trim off the top edge of the felt with a utility knife by running the knife around the perimeter of the box while holding the loose felt up with one hand.