This is for a women's size medium sock; instructions for a 13-inch stocking and baby socks (size 3 to 6 months), respectively, are in parentheses. 

You'll need two 50-gram balls of fingering-weight yarn for a pair of women's socks, one 4-ounce skein of worsted-weight for the stocking, and one 50-gram ball of fingering-weight for baby socks (making three pairs). Review the illustrations as you work; they will guide you.

1. Cuff and Leg
Cast on 60 (54, 30) stitches (sts) on size 2 (6, 2) double-pointed needles. Divide sts among 3 needles with 20 (18, 10) on each (see fig. 1). Knit cuff in rib (k2, p2) for 5 rounds. K only until leg is 6 inches (9 inches, 3 1/4 inches) or desired length from beginning of heel (fig. 2).

Dividing Stitches and Knitting Cuff and Leg
The cast-on stitches are evenly divided among 3 needles. Then the needles are laid flat and the stitches are arranged with the twisted border at the edge of the work, pointing inward. The stitches on the 3 needles are joined using a fourth needle.

The first few rounds are worked in ribbing (k2, p2), then the rest of the leg is worked by knitting every round.

2. Heel Flap
Divide sts among 3 needles again, placing 30 (27, 15) sts on 1 needle for the heel flap and 15 (13 & 14, 7 & 8) on remaining 2 needles for instep. Working on heel needle only, knit in stockinette (k 1 row, p 1 row) for 22 (20, 11) rows; always slip first st of each row. End with a knit row.

Creating the Heel Flap
After the leg is done, stitches are divided again to start heel. A greater number (for heel) are put on 1 needle; fewer (for instep) are put on the other

On needle with heel stitches, you'll work straight rows back and forth, creating a flap that extends beyond the leg.

3. Heel Turning
P15 (14, 8) sts. P1, purl 2 together (p2tog) -- see Decreasing Two Ways -- p1, turn. Slip (sl) 1, k2 (3, 3), k1, slip, slip, knit (ssk), k1, turn. Sl1, p up to the stitch preceding gap created by the slipped st on the previous row, p2tog to close gap, p1, turn. Sl1, knit up to the stitch preceding the gap created by the slipped st on the previous round, ssk across gap, k1, turn. Continue until you have 17 (15, 9) sts on your needle. If you don't end on right side, turn work and knit across.

Turning the Heel
To round off the heel flap and make it curve to fit a foot, a number of short rows are worked back and forth. Decreasing at regular intervals gives the heel its curved shape.

4. Instep and Gusset
Pick up 1 st in each "chain" along the left side of the heel, as shown, and k across. (To avoid holes, pick up an extra st or two at the corners of the instep.) Combine sts from the 2 instep needles, placing 30 (27, 15) instep sts on 1 needle. K across instep sts. Pick up 1 st in each "chain" along the right side of the heel, and k across. Divide heel sts evenly between 2 needles. Keeping in mind that each round begins at the center of the heel, work as follows. On needle 1: k to last 3 sts, k2tog, k1. On needle 2: k across instep. On needle 3: k1, ssk, k to end. Knit 1 round. Repeat until 60 (54, 30) sts remain.

Creating Instep and Gusset
To integrate heel flap into foot, stitches are picked up along left-side "chain" of heel flap. With an empty needle, instep stitches are knit; with another empty needle, stitches along right side of heel are picked up and knit. Stitches remain on needles this way until sock is finished.

5. Foot and Toe
Each round begins at center of heel. Knit until foot measures 7 inches (7 inches, 2 1/2 inches) from back of heel. Then, on needle 1: k to last 2 sts, k2tog. On needle 2: ssk, k to last 2 sts, k2tog. On needle 3: ssk, k to end. Knit 1 round. Repeat until 30 (27, 15) sts remain. Then decrease, as above, every round until 8 sts remain. Break yarn; thread through sts twice. Secure with a knot.

Creating Foot and Shaping Toe
Stitches are arranged correctly, but you have more than you need for a foot's width. The sock is shaped by decreasing. It will look like this before you knit the foot and toe. A few more rows, then you're done!

Duplicate Stitch
Each square on graph paper equals one stitch. Work from bottom up, making stitches taut, not tight. Thread needle with same weight yarn as sock.

1. Insert on inside and come out at base of stitch ("V"). Pass needle behind stitch directly above, from right to left.

2. Insert needle back through the step 1 starting point. Repeat for each stitch; snip yarn and weave ends in at back.