To open a coconut you must first drill a hole on its end, where the so-called eyes are located. You will notice that one of the eyes is usually more fragile and, therefore, easier to drill by simply using a corkscrew or a knife, just like you see in the video.
Turn the coconut upside down and let all the liquid inside it go out. Place the coconut on a glass, with the hole facing down, and let the liquid flow. Attention, this is not milk, but coconut water!
Finally, your time has come: take a hammer and make definite strokes on the coconut. Take the white pulp out of the shell with a knife and remove the fibrous film covering it, using a potato peeler. At this point you can rinse the coconut pieces and use them as you prefer.