A simple crochet hat is sometimes the best. Like for instance this modern and timeless beanie by Rich Textures Crochet in the pictures below. What's more, it's not only super easy and fast to do, but it's also incredibly warm and cozy, while being breathable at the same time.

Photos by Rich Textures Crochet / Ravelry.com

Find original free pattern on richtexturescrochet.com, or read more about it on Ravelry.