I have never done a button hole before, ok here goes...
this pattern was featured on the about.com website, if you are familiar with it this is button hole version 4.
I bolded what I didn't understand.
"Work the required number of stitches before starting the buttonhole.
As if to knit, slip one stitch. Between the tips of the needles, bring the yarn to the front of the work and drop it. As if to knit, slip the next stitch from the left-hand needle to the right-hand needle and pass the first slipped stitch over the second slipped stitch and off the needle. Not using the dropped yarn, bind off the required number of stitches in this manner.
Slip the last stitch on the right hand needle back to the left needle. Turn the work around. Bring yarn to the front. At the edge where the buttonhole was started, using the twisted method of casting on purlwise, cast on one more stitch than the number that you bound off.
Turn the work around. Slip the first stitch from the left hand needle to the right needle as if to knit. Slip the extra cast on stitch over the next stitch and then slip this stitch back onto the left-hand needle."
any help simplifying this would help. I am making wrist warmers and for the thumb I am doing a botton hole. In case it helped to know what i was using the button hole for.