I began with a size F crochet hook and binder rings. I wanted them to be overly large, so I chose the 2.5" size rings.
Begin by crocheting all the way around the ring.
Next row, still in back loops only, decrease 5-6 times evenly spaced around.
Crochet about halfway around (for me, 200 stitches).
Decrease one in the middle,
Chain 1, turn.
Skip first sc, SC across stopping before last sc.
Chain 1, turn, skip first sc. SC across.
Continue in pattern until it tapers to the thickness that you want the band.
Make 2 of these.
That is where my notes end. Ha ha. But, the rest is easy, just crochet the band til it's long enough to go around the hat, then make the little part that goes in the middle, an easy little rectangle.
Obviously too big to wear without the hat.