They are made with embroidery hoops and black felt. Cut the circles of felt larger then then the hoops. Wrap felt around hoop and hot glue in place. Then hot glue the two smaller (ear) hoops to top of head. Minnie was embellished with a ribbon bow. I used wooden hoops but if I were to do again i would get the plastic ones. You can see one of minnie's ears is a little wonky. I dropped it and the wooden hoop cracked.
That simply and I think a great way to display our pins. If you need more help or more detail feel free to pm me.