When you knit a sweater, you have to make the armholes and neck, and the directions tell you what to do to shape them.
Bind off 6 stitches at the beginning of the next 2 rows--bind off six stitches, work to the end. On the next row, bind of six stitches and work to the end. You can't bind off at the end of a row, so you're 'cutting in' for the armholes at the beginning of the two rows.
the two stitches at beginning of following 2 rows--same thing--bind off two, finish the row, bind off two at the beginning of the next two rows and finish the row.
Then you continue on the remaining stitches until the measurement for your size, making the last row you knit a right side row.
Next will come the neck shaping where you will bind off the center stitches. At this point you will have the two shoulders on your needle with the neck sections bound off.
This sweater has you working each shoulder separately, so just follow the directions for each row and I think you'll be fine. If you get confused, by all means ask.