Marking neck line

How do I mark center 28 sts for Back neck.
I have 90 sts on my needle. I am making the Simple Spring
Swing Cardigan that is a knit along project that you can find
on YouTube.

It sounds like they want you to just mark the middle 28 stitches. If you are leaving them all as live loops to do something else with like a 3 needle bind off for the shoulder stitches and using the back neck stitches for the neckband you could use a regular round stitch marker and put it on the needle at the right place. There will be 31 shoulder stitches, 28 for the back neck and 31 more for the shoulder to total 90. If you move them to a spare needle or something just move them markers and all.

Sometimes I think they have you bind off all the stitches and mark the middle ones for where the neck will be and where the shoulders will be for your seams. In that case just run a bit of yarn between the stitches in the appropriate places or maybe use a split ring marker (I have never used these, but I think they would work here).

Thank you very much. This worked. After I marked the center
sts I bonded off. Now working on the left front.