Faux cable stitch is from Super Stitches Knitting.

c/o 70
rounds 1-3: (p2, k3)
round 4: (p2, sl1, k2, yo, psso3)

On round 4 of the 14th repeat, working in pattern, divide between needles for heel.
First, top of foot, 37. (7 columns plus purls on either end)
Then, heel, 33. (7 columns, no purls on the ends)

Over heel stitches only:
S1, purl across (33)
Then S1, K1 across (33)
Turn, repeat for length of heel.

Toe:
When heel needles reach 8 sts, top of foot will have 3 sts more than heel (19 sts.) Dec every row on top needle for last 3 rows (vs. every other) to reach 17 sts.
Then, dec when returning to top sts (k across.) Kitchener from the heel side (16+16.)