This kind of jew's harp can be great to learning, for me the only problems it's that the vibration is not so long, so you can't do really really nice melody.
But it's enought to offer at kids, or at friends, original and relatively easy to do it.
Step 1: What you need.
_1 piece of bamboo, like in the picture.
You can also use exacto, little scisors woods, and lot of other things, but I just want to show you the base, with minimum tools.