Pattern help please!

I’m knitting my first sweater. I have a question about the shaping of the neck in the front piece. I bolded the confusing part:

SWEATER
BACK
With smaller needles, cast on 40 (44, 48, 52); 58 (62, 68, 74, 80, 86) sts. Work in St st for 4 (4, 4, 4); 6 (6, 6, 6, 6, 6) rows. Work in k1, p1 rib for 4 (4, 4, 4); 6 (6, 6, 6, 6, 6) rows. Change to larger needles. Work in St st until piece measures 15½ (16½, 17½, 18½)"; 24 (25½, 27, 27½, 29, 30½)" from beg or desired length. Place all sts on spare needle or holder.

FRONT
Work same as Back until piece measures 13½ (14½, 15½, 16½)"; 22 (23½, 25, 25½, 27, 28½)" from beg, ending with a WS row.
Shape neck: Next row (RS) K 17 (18, 19, 20); 22 (23, 25, 27, 29, 31) sts, [B]join a 2nd ball of yarn and loosely bind off center 6 (8 ,10, 12); 14 (16, 18, 20, 22, 24) sts, k 17 (18, 19, 20); 22 (23, 25, 27, 29, 31) sts. Working both sides at the same time with separate balls of yarn, bind off 2 sts at each neck edge once, then dec 1 st at each neck edge every other row twice. [/B]Work even until same length as Back to shoulder. Work 3-needle bind off on 13 (14, 15, 16); 18 (19, 21, 23, 25, 27) sts for each shoulder seam. Bind off center Back 14 (16, 18, 20); 22 (24, 26, 28, 30, 32) sts.

I just go :eyes: when I read that. Join the second ball how/where? Work in both sides at same time? Eh? I’m totally confuzzled. Can anyone help?

Thanks!

You’re going to start working each side of the neck separately, so the sweater doesn’t cut straight across.

Knit across the first number of stitches for your size, and let that yarn drop. Now with a new skein, bind off the center stitches. Just start knitting with it and leave a tail to weave in later. The binding off will secure it. Then with the new yarn, work the rest of the row.

Now you have a strand of yarn on each side of the neck, and you’ll work one side, then the other with a space in between.