I have finally successfully set the collar and knit up the collar. I sewed the steeks on the collar and had a bit of trouble with fraying. So, I tried crocheting the steeks for the left sleeve. It has worked beautifully. One thing: the smaller and tighter the crochet edge, the better the steek will hold. I used a 2.00 mm crochet hook with this sweater and it is VERY stable now.
The sleeve steek before I crocheted and cut: