This hat is created bottom up, and you can create this with any yarn of your choice. However, I created this using 2 balls of different colored Plymouth Gina Yarn. Alternating the balls of yarn every two rounds allows for the self-patterned striping which looks unique when done! Since Gina is a lighter weight yarn, I used a size F hook to create the hat. If you choose to use heavier yarns, and/or a bigger hook size, make sure that your initial chain is big enough to fit around your head (where you want the hat to fit). The FHDC crochets up a little tighter than regular HDC, so please take into account that your hat will not be as “elastic” as you are used to creating using regular crochet stitches. I have written the pattern for an adult female head, and it can be adapted to fit any head size as long as you adjust the initial chain according to the fit.