Use sharp pruners, loppers, or a hacksaw to cut short, even lengths of bamboo stalks. Don’t worry about the thickness of the bamboo stalks; the natural variation in size will attract a range of different bee species.
Fill the base of a small terra cotta pot with a thick layer of modeling clay and push the cut bamboo stalks into it. Continue until the pot is full and the stalks are sitting snugly inside the rim.
Stuff the gaps around the stalks with moss or dried grass to hold them firmly in place. Try to ensure that all stalks are pointing toward the ground, so that rainwater does not pour into the holes.
Tie a piece of raffia or gardening twine around the pot and use the excess twine to make a loop for hanging the pot from a hook. Or attach it to a wall in a sunny position sheltered from the wind, close to nectar-rich plants.
Tie the raffia or string loosely around the base of the pot and then carefully push it upward, toward the rim. As the sides of the pot widen, so the hold tightens.