Note: If you prefer knitting on two circulars, Rob has provided alternate directions in a Word doc. Click here to download.

Garter Ripple Stitch:

Round 1: *K2, yo, k3, ssk, k2tog, k3, yo, k2; repeat from * around.
Round 2:Purl.

Ripple Stitch:

Round 1:*K2, yo, k3, ssk, k2tog, k3, yo, k2; repeat from * around.
Round 2:Knit.

Cuff

CO 56 sts loosely.
Divide sts on 4 double pointed needles [14 on each].
Join in the round without twisting.
Work in Garter Ripple Stitch for a total of 6 pattern repeats [12 rounds].

Leg

Switch to Ripple Stitch and work these two rounds until the entire sock is 7 inches long [or desired length] when measured from cast on edge.
End with a pattern round [Round 1].

Heel Flap

Slip N2 stitches onto N1 -- 28 sts. Slip N4 stitches onto N3 -- 28 sts.
With RS facing, work back and forth as follows:
Row 1: *Sl 1, k1. Repeat from * to end.
Row 2: Sl 1, purl across.
Repeat these two rows 17 times.

Turn Heel

Rw 1: [RS] K17, ssk, k1. Turn.
Rw 2: Sl 1, p7, p2tog, p1. Turn.
Rw 3: Sl 1, k8, ssk, k1. Turn.
Rw 4: Sl 1, p9, p2tog, p1. Turn.
Continue shaping the heel as above, adding one additional st in the middle each time [K10, P11, K12, etc.] and decreasing 1 st as directed [ssk or p2tog] until all sts have been worked. End with a purl row. 18 sts remain.

Gussets

Knit across the heel stitches. Do not turn. Using the same needle [N1], pick up 1 st in each edge stitch along the side of the heel flap [the right side should be facing you] for a total of 17 stitches.
Pick up 1 additional st in the gap between the flap and the instep sts [those "on hold" since starting the heel flap]:36 sts total.

N2 [instep stitches]:knit across:28 sts.

N3:Using another [empty] needle, pick up and knit 1 st in the gap between the instep sts and the heel flap.
Pick up 1 st in each edge st along the other side of the heel flap for a total of 18 sts [1 in the gap + 17 along the flap].
K 9 sts from N1 onto N3 -- 27 sts total.

You are now at the beginning of your round, with half of the turned heel stitches and one gusset on N1, the instep/pattern stitches on N2, and the gusset and the other half of the turned heel stitches on N3.

Round 1:
N1: Work to 3 sts from end, k2tog, k1.
N2: Cont in pattern by resuming Ripple Stitch pattern from above [round 1].
N3:K1, ssk, work to end.

Round 2:
Work even.

Repeat these 2 rnds until there are 56 sts remaining [N1:14 sts, N2: 28 sts, N3: 14 sts].

Foot

Work even, keeping only the instep stitches [N2] in Ripple Stitch until the foot measures 1.5 -2 inches less than the desired foot length [approximately 9.5 inches for a women's US 8 shoe].

Toe

Round 1:
N1: Work to last 3 sts, k2tog, k1.
N2: K1, ssk, work to last 3 sts, k2tog, k1.
N3: K1, ssk, complete round.

Round 2: Work even.

Repeat these two rnds until 20 sts remain [N1: 5sts , N2: 10 sts, N3: 5sts].
K sts from N1 onto K3. You should now have 10 sts on each of 2 needles.