This is a simple FPDC/BPDC ribbed hat. This pattern works up quickly and makes a nice stretchy rib.

The pattern is easily customized to adjust size and fit, by adding multiples of 4 ch to the beginning chain, and adding rows for length. When adding ch to the pattern for a larger hat, it will add to the number of decreases in the decrease rows, so adjust accordingly.

Any weight yarn can be used, with slight adjustments possibly needed for sizing. If you use a worsted/medium weight yarn, consider using a size I or J hook.