Step 1: Choose you bamboo
First thing you need to do is to choose the piece of bamboo you want to use. I sugest one that has a very straight and prefferably a very flat side to it around the node. The node is where two sections of bamboo meet at.
The piece I chose has been dried already. I do not suggest using a piece of green bamboo for this project. As it dries, it has a higher tendency to split or warp slightly which will change the tone and sound of the bamboo greatly.
Step 2: Cut your Bamboo
When you cut this bamboo, you want to cut about an inch above the node you will be using, and several inches below it as well. This should give you a piece of bamboo that's just about the length of your hand (fits in pocket). If the bamboo still has branches and leaves they should be cut as close to the body as possible and sanded down flush, as in the picture.
Step 3: Clean out the bamboo.
Using another piece of bamboo as a sort of bottle brush, clean out the layer of white from the inside of bamboo. Be vigorous to get all of this lining out as it will help to prevent molding and will help air flow later on in the project. Be sure to do both ends of bamboo, and be carefull not to knock the node out or poke a hole in it by accident.