Abbreviations:

K, k	Knit
P, p	Purl
st, sts	Stitch, stitches
CO	Cast on
DPN(s), dpn(s)	Double-pointed needles
Sl	Slip
K2tog, k2tog	Knit 2 together (a 1-stitch decrease)
P2tog, p2tog	Purl 2 together (a 1-stitch decrease)
SSK, ssk	"Slip, slip, knit": Insert right needle into the next st as if to knit, but slip it from the left needle to the right needle without knitting it ("Sl 1 knitwise"); Sl 1 knitwise (that is, repeat the first operation); insert point of left needle into the two slipped sts, in front of the right needle, and wrap the right needle to knit them together from this position (a 1-stitch decrease).
*...*	Repeat the instructions between the asterisks for the rest of the round, unless otherwise directed.
Special Abbreviation:
T2F	"Twist 2 right": Slip next stitch onto a cable needle and hold it at the front of the work. Knit the next stitch from the left hand needle then knit the stitch held on the cable needle.

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Materials: 4oz bag of mixed merino roving. Purchased from Get Knitted (similar bags are available on EBay)
2.5mm (US 1) Clover bamboo DPNs or 2 2.5mm 24-inch circular needles or 1 2.5mm 40-inch or 47-inch circular needle
Stitch marker
Stitch holders or waste yarn

Gauge: 8 sts and 12 rounds to 1 inch in pattern.

Cuff:

In main colour, CO 72 sts loosely on 2.5mm dpns. I usually cast on using a cable cast-on while holding two needles in my left hand. This gives me the required looseness while still keeping a neat edge.

Divide these stitches equally among 4 dpns (18 sts per needle), or you can use two circulars, or magic loop on one long circular, if one of those is your preferred method. Place a stitch marker to mark the beginning of the round.

Rounds 1-12: K.

Rounds 13-21: Join in the contrast colour and work row 1 of chart 1, beginning at the lower right corner, repeating 12 times around the sock, remembering that as you are working in the round you will always work each row of the chart from right to left. Continue working the chart until you completed all 9 rows.

Rounds 22-57: Break off the contrast colour and start the twisted stitch pattern in chart 2, also beginning at the lower right corner, repeating 12 times around the sock, and always working from right to left. Work the rest of the chart and continue in this pattern until the work measures 5" ( 13 cm) from the beginning of Chart 1 (the checkerboard pattern); then work remaining rows of chart to end with Row 6 of chart 2.

Work the heel flap:

Still using the main colour, k18, then turn your work Rejoin the contrast colour and p36. Place the remaining 36 sts on stitch holders or waste yarn and continue on the 36 sts that have just been purled in the contrast colour as follows.

Row 1: *Sl 1 , k1* across the 36 stitches.

Row 2: Sl 1, p35.

Repeat these two rows 16 more times.

Turn the Heel:

Row 1: K23 stitches across the heel, ssk, turn work.

Row 2: Sl 1, p10, p2tog, turn work.

Row 3: Sl 1, knit to within 1 stitch of the gap, ssk, turn.

Row 4: Sl 1, purl to within 1 stitch of the gap, p2tog, turn.

Repeat rows 3 and 4 until all the heel sts have been worked, ending the last repeat with just an ssk and a p2tog. There are 12 heel sts left.

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Heel Gussets:

Round 1: Knit across the 12 heel sts and then pick up 17 sts down the side of the heel flap. Knit across the 36 sts of the top of the sock and then pick up a further 17 sts up the other side of the heel flap.

Organise the sts from the heel and the gusset so that you have 23 sts on the gusset needles 1 and 4, while keeping the 36 sts from the top of the sock on needles 2 and 3 (18 sts on each).

Round 2: Work to within 3 sts of the 1st needle of the round (containing 23 sts), k2tog, k1. Work the two instep needles, k1, ssk, at the beginning of the 4th needle. work to the end.

Round 3: K.

Repeat Rounds 2 and 3 until there are only 16 sts (not 18) left on the two gusset needles (68 sts in all). This stitch reduction is necessary because the travelling stitch pattern on the cuff draws the knitting in; if you were to keep the same number stitches for the foot in stockinette stitch, the foot would be rather baggy.

Once the decreases have been completed, continue to work the rounds in stockinette stitch until the foot measures 2 inches less than your desired finished length.

Shaping the Toe:

Rearrange the sts so that there are 17 sts on each needle by slipping 1 stitch from needle 2 onto needle 1 and 1 stitch from needle 3 to needle 4.

Round 1: Knit to within 3 sts of the end of needle 1, k2tog, k1; k1, ssk at the beginning of needle 2; knit to the end of the needle. Repeat over needles 3 and 4.

Round 2: K.

Repeat these two rounds until you have 5 sts left on each needle (20 sts in all). Graft the remaining sts to close the toe.

Repeat the instructions above to knit a second sock.