Knit in the round in seed stitch beginning with a 16” circular needle and switching to double pointed needles at the crown. You will need one stitch marker.
Yardage requirements will differ for each of the three yarns. One skein of each yarn will make one hat.
This pattern has instructions for the three different yarns you can choose from.

Trendsetter Me - 1 skein
Claudia Handpaints Chunky - 1 skein
Ella Rae Lace Merino - 1 skein, held double