This hat is clearly related to EZ tri corner ski cap, and to the sweet baby cap, with closer to the head shaping.

The pattern uses Raised Center decreases, (no directions for this are included) there are links to on line tutorial --or use your favorite reference book.

The suggested cast on is the Channel Island cast on.. NO directions are included, but there is a link to a YouTube tutorial.

The design is one size fits most, but you can adjust it smaller by using smaller needles and DK weight yarn, or larger needles and Aran weight yarn.