Provisional cast-on: chain 70 using the scrap yarn. Break yarn and pull it through the last st. Using Venla and the larger needles and beginning at the sixth st on the chain, pick up and knit 1 st per ch until you have 60 sts in total (15 sts per needle).
Work stockinette stitch in the round for 3 rounds. Picot round: *k2tog, yarn over*, repeat *–* to end of round. Work stockinette stitch in the round for 3 rounds.
Unravel the crochet chain and place the released sts onto the smaller needles. Make sure you pick up each released st = 60 sts. Fold the piece once so that the cast-on edge is on the inside and the larger needles are on the outside. Knit the sts on the smaller and larger needles together: knit the 1st st on both needles together using the larger needle. Work the 2nd pair of sts in the same manner. Continue until all pairs of sts have been knitted together = 60 sts.
Begin the lace pattern on row 1 of the chart. Repeat the 15 st pattern 4 times. Work rows 2–10 of the chart.
Switch to the smaller needles and knit 1 round, then purl 1 round (fold round) and knit 1 round. Turn the WS out.
Work ribbing in the round for 2,5 cm, then work stockinette st.
When the leg measures 15 cm from the fold round, begin heel flap: knit the sts on needle I onto needle IV = 30 sts. Leave the other sts on hold and turn work. WS: p30, turn work.
Reinforced stitch pattern:
Row 1: (RS) *slip 1 with yarn in back, k1*, repeat *–* to end. Turn work.
Row 2: (WS) slip 1 with yarn in back, purl to end. Turn work.
Work rows 1–2 a total of 15 times (= 30 rows).
Begin French heel turn:
Row 1: (RS) slip 1, k16, skp (= slip 1 knitwise, k1, pass slipped st over), k1. Turn work.
Row 2: (WS) slip 1, p5, p2tog, p1. Turn work.
Row 3: slip 1, knit to last st before gap, skp, k1. Turn work.
Row 4: slip 1, purl to last st before gap, p2tog, p1. Turn work.
Continue in this manner until all sts have been worked. Redistribute the remaining sts onto two needles.
Using a free needle pick up 15 sts from the left end of the heel flap + 1 st from between the flap and needle II. Using the left-hand sole needle knit the heel flap sts and knit the picked-up sts through the back loop. On needles II and III work stockinette st as established. Using the right-hand sole needle pick up 15 sts from the right end + 1 st from between needle III and the heel flap. Knit the picked-up sts through the back loop and knit the heel flap sts. Now work stockinette st in the round with all sts.
At the same time begin gusset decreases: at the end of needle I, k2tog; at the beginning of needle IV, skp. Repeat the decreases every other round until 15 sts remain on needles I and IV = 60 sts.
Work stockinette st until the foot measures approx. 19 cm or until the sock covers the fifth toe.
Begin toe decreases: at the end of needles I and III, k2tog, k1; at the beginning of needles II and IV, k1, skp. Repeat the decreases on every other round 8 more times. 6 sts on each needle. Redistribute the sts onto two needles, 12 sts each on instep and sole. Graft the sts together.
Knit the other sock in the same manner.
Securely weave in all ends. Fold the lace edge out. Lightly steam the socks.