Breaking yarn and rejoining

Hi There,
I wonder if you are able to help me? I have a pattern for a simple pull-through scarf which has an opening in the middle to pull one end of the scarf through. I understood all of the pattern until the opening. If I may just give a few instructions, perhaps you can make it clear to me what I should be doing??

Row 49: K13,turn.
Row 50: K6, turn work & cont on 6 stitches just knitted, leaving rem sts on needles.
K8 rows.
Break yarn & leave sts just knitted on stitch holder. Rejoin yarn to 7 sts on LH needle on RS of work.
K3 rows.
Next Row: K2, p to end.
K3 rows.
Next Row: K2, p to end.
K2 rows.
Break yarn & add sts to those already on stitch holder. Rejoin yarn to 7 rem sts on WS of work.

I hope this is not too much to ask! I understand the abbreviations etc but I have knitted it several times and am clueless about the breaking yarn and rejoining it. I am think I am supposed to be forming an opening like a large buttonhole.

I hope you can maybe make it a bit clearer.

Many Thanks!