Time to adorn your hair with bright red felt flair.
You may want to cover the stapled hem with cloth tape to shield staples' open tips.

Cut out red felt according to shape and dimensions of how-to picture.

Staple hat halves together along the curved edge at least 1/2" in from the outside. Leave the the 5" of the short straight edge unstapled.

Turn hat inside out and staple halves together along the short straight edge.
Fold up the bottom of the hat to create the brim.
Cut two small slits, one 1 1/2" above the other, on one side of the hat just below brim level.
Thread feather stem in and then out of the holes.
Attach gems, googly eyes, and pipe cleaners to hat with mounting tape.