Cut a sheet of plywood to use as the backboard of the display case. The exact size to cut the plywood depends on the width and height of the jersey. The backboard should be 4 inches wider and taller than the maximum jersey measurements.
Build the sides of the jersey display case using four 1 by 2-inch boards. Cut two of the boards the same length as the sides of the backboard. Cut the remaining two boards the same length as the top and bottom of the backboard.
Use a saw to make 45-degree cuts on both ends of each 1 by 2-inch board.
Place wood glue on the bottom of each 1 by 2-inch board. Position them along the backboard to create a frame. Nail them into place.
Paint or stain the wood to achieve the desired color.
Trim a piece of batting and fabric so each is 2 inches wider and taller than the backboard of the display case. Using fusible tape, hem the edges of the batting and fabric 1 inch so you won't see frayed or unfinished edges. Use spray adhesive to glue the batting and fabric to the backboard.
Center the jersey in the display case, and pin the jersey to the fabric to hold it in place.
Attach a piece of 1/4-inch thick plastic glass, cut to the same size as the backboard, to the frame of the display case using acrylic cement.
Fasten a piece of hanging hardware to the back of the jersey display case.