This is a beginning brioche pattern. You begin with smaller needles for the brim and change to larger needles for the remainder of the hat. You need two contrasting color of DK weight yarn -- one light and one dark. If this is your first try at brioche, make sure there is a lot of contrast!

Because you are casting on with the smaller needle, make sure you are capable of casting on loosely!

I have videos in YouTube to help you out.

Basic Brioche: https://www.youtube.com/watch?v=RExCN8Reemw

Increases: https://www.youtube.com/watch?v=K-h0o_5zHio&t=164s

Decreases: https://www.youtube.com/watch?v=tUtZfoiCRb4&feature=y...