This is one of my favorite things to do with those neat buttons where you only have one or two left on a card. I use the shank ones, but you *can* use the ones with holes.
Pick out about 25 of them. String them on an 8" piece of black cord elastic, the thickest you can get through the button's holes. If you're using a button with surface holes, go through from the bottom, across the top and down, threading on a pretty bead if you like. When all the buttons are on, knot securely to fit whatever wrist it's intended for and seal knot with a drop of waterproof fabric glue or Super Glue.
You'd be surprised how pretty these are. I always get compliments when I wear one (and usually wind up giving it away.)