Is it a hat or a wig or perhaps a helmet?
Whichever it is, it is knitted side to side in rows and the shaping is done with short rows. Because of the nature of alternating stockinette with reverse stockinette, this hat will stretch to fit any size adult head.

This is an intermediate level pattern. It includes short rows and knitting with 2 colors.

Yarn:
Main Color (MC) for the stripes: approximately 100 yds worsted weight
Background Color (BC): approximately 90 yds worsted weight

Use any yarn, but wool will make a very heavy and very warm hat, so it might be best to choose a synthetic yarn for this project. Also, since the hat is knitted side-to-side, it will tend to stretch lengthwise when blocked, and that will be much more pronounced with wool than it is with acrylic. If using wool, make sure you have a tight gauge.

The rainbow colored sample is knitted with
MC: 75g Hobii Carnival 100% acrylic, held double
BC: 40g Yaoh-wool 100% acrylic