YOU WILL NEED
Flatten one end of the straw between your fingers. Using the scissors, cut the corners of the flattened end of the straw.
Put your lips on the straw with the open parts to the sides of your mouth.
Bite down with your lips a little bit and blow. You should hear a buzzing sound. If not, try: moving your lips a bit up or down the straw; tightening or loosening your lips; or recutting the straw at a slightly different angle.
When you have gotten a good steady sound, cut some tone holes (4 holes is about right). Using the scissors, make a cut in the middle of the straw at an angle, and then from the other side until a diamond-shaped hole appears.
You can also use a hole punch. Pinch the straw where you want the hole, and put just a bit into the very edge of the punch. The idea is keep the holes small enough to have the straw keep its stiffness as a tube, yet big enough to enable easy pitch change.