Cut out some felt. Um, collar size.
get ready to sew
Sew ribbon around edge. It's decorative and adds strength.
iron iron iron
and iron some more
now stitch. Folding the material down as shown makes the collar a little more 3-dimensional
iron.Notice that the flaps of the collar stick out a little.
Cover the seam with ribbon.
Here I've used that iron-on glue stuff to stick a piece of Velcro to the back. The back of the silver beacon tag in the picture has a corresponding piece of Velcro.