Determine which patches you want on your hockey jersey and where you want them placed. Patches with a version of the team's logo can be placed on the shoulders of the jersey's sleeves. Patches that reflect the league you are playing in, such as an NHL commemorative patch to symbolize playing in the playoffs or the Stanley Cup Finals, often are sewn over the right or left breast above the team logo on the front of the jersey. If a player is a team captain or alternate captain, the letter "C" or "A" is customarily sewn on the upper-left breast.
Place these patches exactly where you want them on the jersey. Use a needle and thread to lightly sew the patch onto that part of the jersey just secure enough that it stays in place. Make sure this thread is the same color as the rest of the jersey to help it blend in.
Load nylon thread -- stronger than regular sewing thread -- into a sewing machine. Sew the patches securely onto the jersey. Cross stitch all along the sides of the patch to ensure it is not loose around the edges. Make sure the nylon string is the same color as the rest of the jersey to help it blend in.