Help with Sahara pattern

I am making the Stitch Diva’s Sahara. I started with a provisional caston with waste yarn and have knitted 6.5 inches in St st. I have 92 stitches on the needle which is correct it says “Place sts on holder and break yarn” which I have done.

Now this is where I get really lost:

Slip outer 24 sts from each end of the provisional cast on back to larger needles leaving center sts on holder. Place a clip-on marker on this row to mark the top of shoulder. Beginning with a RS row, attach A and work across right shoulder. Drop yarn, attach a second ball of A and work across left shoulder. Work two shoulders seperately yet at the same time in St st until measure 3" from clip on.

Okay I have my circular needles, do I go to my first row where the waste yarn is, pull out 21 sts and put them on the needle. Then do I on the other end of my first row, pull out 21 sts and put where??? Then it says leave center sts on holder. Does it mean the provisional cast-on waste yarn leave on the sts. Those are not the stitches i put on the stitch holder.

I have attached a picture of what I have done so far.

Slip the first 24 of the provisional stitches onto your circular. Lace a piece of yarn through the center stitches as a holder to keep it easy to maneuver, and then slip the end set of 24 onto the same needle.

You’ll have 24 stitches, a gap where the stitches are on hold, and then 24 stitches.

With the right side facing you, knit across the first 24 (left shoulder) with one ball of yarn, then across the second set of 24 with a separate ball of yarn.

Now you’ll have a ball for each shoulder.

Thank you so much. You explained it well for me.