I first got the idea from my old friend Kyt, who got some rainbow buttons from eBay and strung them into an elasticated bracelet years ago. I searched DIY tutorials and simplified them to hell so even a simpleton like me could handle it.
These I made as Christmas presents in each of my friends' favourite colours. With it, I threw in a bead ring (which I did not make but found for £1 each from Edinburgh Woolen Mill,) which I packaged in a (terribly hand-sewn) drawstring pouch.
I've always had a great appreciation for presents handmade by the giver, as I know how time-consuming and personalised it can be. In primary school I had bags of time for making presents, but I made these well in advance, not that they take long to make - 5, 10 minutes?
The hardest bit is going to the indoor market on a Saturday to get the materials. 16 buttons from the haberdashery shop with the smiling Indian lady, and 50cm of narrow ribbon. I am so lazy and cheapo there isn't even a proper fastening - the ribbon's just tied in a butterfly knot.
Arrange 2, 8-button-long sequences (I like to arrange them so no 2 identical buttons are adjacent), and thread them onto the ribbon, first with it facing you and the next, with it facing away, taking from each sequence alternately. Tie a couple of knots in the ends so the buttons can't go awandering. That's it.