I will try~ but I am not 100% positive I know what I'm doing
I would bind off and each time I drop a bound stitch OFF the needles I would count that as ONE bound off stitch. By that I mean the one that is pulled over the stitch ON the needle~clear as mud? LOL. Then God willing I would have the right number of stitches left to work, whatever the pattern said (3 on either side, right?).
Plus, if you bind off loosely enough you can go back and redo it if necessary. Don't worry, you can do it!
hope that helps!