Grab another piece of felt and trim it to about 1″ square. It can be any color you like, since it’s going on the back. Use your needle and thread to secure the safety pin to your square of felt, like in the photo above. Then, put some fabric glue on the other side of the felt square to glue the pin to the back of your badge. You’ll want to glue it fairly close to the top, so the badge doesn’t flop when your little superhero puts it on.