I used raffia purchased from Papermart.com. Raffia tends to stretch, so make your stitches tight.

You can also crochet the hat in cotton yarn. I recommend Lion Brand Cotton Ease Worsted Weight 4, 3.5 oz/100g, 207yd/188m

Contrasting raffia or yarn for the embroidered flowers.

You’ll need a tapestry needle to weave in ends.

Also, a stitch marker.

Stitches used:
CH (Chain)
SC (Single Crochet)
SL ST (Slip Stitch)
RSC (reverse single crochet or crab stitch)