Fresh bamboo shoots can be delicious, but they are somewhat toxic and strongly bitter if not prepared properly. Note that different types of bamboo may require more or less time for cooking or soaking, but the following method is sufficient for common varieties.
Start by peeling off the tough outer layers. Divide the shoot into halves.
Boil the bamboo shoot for about one hour, then drain and let cool.
Slice the bamboo shoot into small, thin pieces. If you will need it sliced a certain way for a recipe, go ahead and slice it as needed at this stage.
Soak the shoot in fresh water at least overnight, then drain again. If it still tastes bitter, it needs to soak longer. continue soaking until bitterness is completely gone, usually about 24 hours total.