Bind off who in the what now?

I finished the first pedicure sock, but I had a little trouble figuring out how to bind off in pattern (which really sounded like it shouldn't be that hard), so I gave up and went to sleep. I will look up some better directions and try again tonight. My Stitch 'n Bitch book is in a box somewhere so that is no help. :oP I can see how to bind off a knit row, and how to bind off a purl row, but binding off a knit 2 purl 2 rib in pattern has totally confused me. So far my internet searches have just turned up things to the effect of "Here's how you bind off a knit row. Here's how you bind off a purl row. You can also bind off 'in pattern' by alternating purl or knit stitches according to your pattern." Which I could figure out, so that doesn't help me. My big problem is switching between the knit and purl to bind off. This must be simpler than I'm making it. -_-