Press a quarter in the slot under the head. I also put a slot for a magnet to retain the cap after use, these ones from Amazon work really well: http://www.amazon.com/gp/product/B001KUWM3C/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 Works pretty well, sits innocently on your kitchen counter 99% of the time, but is really handy when you want your beer and you want it now!