Please note, per designer, there is a pattern error:

When you knit the average size (only- the wide size has the correct numbers), increase the stitch number to 66 after the ribbing. Work the cuff and heel as written (the heel over 30 sts), and the foot. Omit the decrease 4 sts rnd. On the first toe decrease rnd: K9, K2 tog,* and repeat as per the instructions.