This hat is knit in the round and I suggested bulky for this pattern but you can use any worsted and just add stitches to the cast on.

12/19/2020 update I forgot to note that the bulky yarn I used should be a single ply bulky. More like a heavy worsted. I had noted my bulky as a suggested yarn but edited the yarn suggestion to reflect a SINGLE ply yarn.
Thank you for your support
Laura