Tape together the two pattern pieces, and compare the bottom measurement with your head measurement. You may want to adjust the pattern to be larger or smaller to suit your needs. I made the pattern extra long so I could fold the excess to the inside. You can decide how long you want the hat as well!
Trace the adjusted pattern onto your fabric.
Add 1/2" seam allowance all the way around and cut out. You'll want to cut out two pieces.
Sew the pieces together along the curved edge, leaving open along the bottom.