Hi folks, I’m making a sweater for dd (first project in 20 years lol, good grief is it going slowly!!). I’ve gotten stuck on the front neck, one side and shoulder is done with the rest of the stitches on a thread. The pattern is telling me to ‘leave center 15 sts on thread, with right side facing rejoin yarn at neck edge of remaining 19sts and knit to end’. I know what it wants me to do but sadly have no clue how to do it Can anyone help with how to rejoin the yarn??