Shaping armhole

Bind off 6 sts at beg of next 2 rows (41) sts.

Not sure how to interpret this. Can someone help? Do I work 2 rows then bind off. Not sure?

It means to bind off when you begin the next row you are going to knit. Bind off the first 6 stitches in the row, the same way you would do to bind off a project. Then finish out the row. On the next row also bind off the first 6 stitches. The (41) is telling you that after you have done the bind offs of those 6 stitches twice you will have 41 stitches left.