Using Joey’s measurements as he is very similar size feet!
8 sts x 10.75” around leg (just below calf muscle) = 86 sts - 8 sts (for negative ease) = Cast On 78 sts.
K2, P2 rib for 2 inches.
Knit the leg in stockinette stitch until sock leg is a total of 6 inches (including both ribbing and stockinette).
Work “sturdy heel” over 38 sts for 3.5 inches (until heel flap is square).
Turn heel: 14 sts on each side, 8 sts in the center, on first row of heel turn.
Work the foot. Dad wears size 9 or 9.5 shoe.
Knit the foot until it measures 9.25 inches long from back of heel, then work the toe. Finished total foot should measure 10.5 inches from back of heel to tip of toe.
Graft the toe together with Kitchener stitch.
Great tutorial on Kitchener stitch by Purl Soho: http://www.purlsoho.com/create/2013/11/11/kitchener-stitc...