Chopsticks usually are to long to use in your Hair, so the first thing to do is to short them a litle bit. How much you cut of depends on how thick and long your hair is, but in general they should be about 15 - 18 cm long.
After that use the drill to make a small hole at the thicker end.

Now point the end opposite to the hole with a pencil sharpener.

Then take a pice of sandpaper and sand all rough parts.

Now paint them. I've tried several paints, even nailpolish works.
But something waterproof might pay off, otherwise use glaze. ;-)

After that pull a piece of thread through the hole and and knot it, so that both ends are equally long. (Or not, if you want a little asymmetry. ^^)

Now add the beads and prevent them from falling down with crimp beads.

Use them for your bun. ;-)