Glazed Tiles features a geometric colourwork pattern that is inspired by the rooftops in the Burgundy town Dijon. It is knitted from the crown down, so you will not have to decide on the size right away. Indeed you could start with any yarn and a gauge that is not exactly the one indicated and stop when the top is large enough for your head.
You can find the hat pattern with all the information on yarn weight, gauge and techniques in my Ravelry store (Click).