Cardigan with collar in lace rib pattern

How to knit the cardigan in lace rib pattern:

Sizes: US 8/10, UK 10/12 / US 14/16, UK 16/18.

Materials:
800/900 g mélange yarn (100% cotton, 60 m/50 g); straight and circular knitting needles size 9 mm (US 13).

Garter stitch: Knit all stitches in right side and wrong side rows.

Reverse stockinette stitch:
Row 1 (right side): Purl stitches.
Row 2 (wrong side): Knit stitches.

Lace Rib Pattern:
Row 1 (right side): 1 edge st, 1 purl, * 1 purl, 1 yo, k2tog tbl (knit 2 together through back loop), 1 knit, 1 purl, repeat from *, end with 1 purl and 1 edge st.
Row 2 and all even-numbered rows (wrong side): 1 knit, * 1 knit, 1 yo, k2tog tbl, 1 purl, 1 knit, repeat from *, end with 1 knit and 1 edge st.
Work Rows 1 and 2 once, then repeat Row 2 throughout.

Gauge: 13 sts and 15 rows = 10 x 10 cm.

Back:
Cast on 62/72 sts and work in lace rib pattern.
After 61 cm from the cast-on edge, mark the beginning of the armholes on both sides and continue straight.
After 17/19 cm from the beginning of the armholes, place the center 30 sts on a holder for the neckline and bind off 16/21 shoulder sts on each side.

Left Front:
Cast on 33/38 sts and work from the right edge as follows: 27/32 sts in lace rib pattern, 6 sts in garter stitch for the front band.
Mark the armhole on the right edge at the same height as the back.
Bind off shoulder sts on the right edge at the same height as the back.
Place the remaining 17 sts on a holder for the collar, leaving the yarn end to continue working later for a neat join.

Right Front: Work symmetrically to the left front.

Sleeve:
Cast on 37 sts and work in lace rib pattern.
For the slopes, increase 1 st in reverse stockinette stitch on both sides in the 13th/7th row from the cast-on edge, then increase 1 st in reverse stockinette stitch every 12th/8th row 4/7 more times = 47/53 sts.
After 50 cm from the cast-on edge, bind off all stitches.

Finishing:
Sew seams, sew side seams up to the marker respectively.
Place all held stitches on circular needles = 64 sts.
For the collar, continue working as follows: continue working the band in garter stitch over the first and last 6 sts respectively, work the 52 sts between them in lace rib pattern.
After 22 cm from the beginning of the collar, bind off stitches in pattern.