EZ seamless sweater back-of-neck shaping - HOW?

I am making my baby a sweater based on the EZ percentage system. This went swimmingly until I got to the neck shaping. I just don’t understand the directions. She writes “Let us take it that you have decided on a K1, P1, rib for the neck border, Starting at left shoulder, turn, and work back to right shoulder in K1, P1 for 40 (1/2 total) stitches”. Here’s my first question: is this the BACK that I am working only - back and forth as if I were not working in the round?*
She then writes: “Slip all first stitches. Turn”. *****Here I almost am in tears. I don’t know WHAT I am slipping. What are all first stitches at this point? I am further confused by the fact that the directions go on to describe picking up 2 stitches/row each time I turn - so I am terribly confused - where I am getting these extra stitches?
If this weren’t my first-born child I am making the sweater for I might offer to give him to anyone who might help, but I love him far too much. I’ve viewed other posts on neck shaping but can’t seem to figure this out.
Thank you

Which book and page is this from? I think I might need to study this for a while. :thinking:

From Knitting Without Tears - the 1st pattern for the seamless sweater-
I do appreciate the irony that I am almost driven to tears…

I think I’ve got it. She’s having you make the back neck of the sweater deeper than the front. So you’ll work across the 40 stitches (or whatever stitches you have for your sweater–half the total around). Then you turn the work and rib back, but when you get to the end of the original 40 you take on another stitch, slipping it, from the stitches on the needle. Rib back and do this again, slipping on stitch on the end from the stitches on the needles that haven’t been worked in ribbing yet. When you get to 52, I think it was, you then rib all around the neck for an inch.

OK, this makes sense. Bless you! I will let you know how it turns out.