Measure the jersey to pick the correct sized frame. Most jerseys fit in a 30-by-36-inch or a 32-by-40-inch frame.
Lay the jersey out on the matte backing board in the desired position. Iron the jersey flat so that the player name, number and sleeve patches are visible.
Temporarily pin the jersey to the mat board. Use stainless steel pins that do not damage jersey fabric.
Stitch the jersey to the mat board. Sew below the neckline, at the start of each sleeve and at the bottom hem. Make sure the thread is through the back of the jersey and does not show on the front. Close the shadow box, and hang it up.