This is a simple cable-and-bobble hat, named in part after one of my favorite designers who does beautiful work in cables, and after the tool, the lucet, which is shaped like the cable, and is used to make cord.
This hat begins with the Estonian sock cast-on, which you can find demonstrated by Nancy Bush on youtube.com. The bottom of the hat is very, very stretchy, and works very well with the cable pattern. After the cast-on and the first two rounds are done, the pattern begins.
The cable-and-bobbin pattern is very easily memorized, consisting of 13 stitches and 8 rounds.
If you want, you can embellish the top of the hat with a pompom, and it will still look pretty darn good!