Pilih tempat yang tepat untuk menyelam. Ambil posisi vertikal di dalam air dengan kaki mengarah ke bawah. Tarik napas perlahan dan dalam untuk mengisi paru-paru dengan oksigen. Ambil posisi meringkuk. Benamkan tubuh Anda. Kembalilah ke permukaan.

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You can completely submerge yourself in any body of water that is higher than you are tall, or that will cover your head when sitting (or even lying down, such as in a wading pool). The most important factor to consider for picking a spot is to observe your surroundings. Always approach holding your breath underwater with caution, especially in a crowded public pool where people are engaged in many different activities and not paying attention to others.  If you want to sink to the bottom of a pool, you may think choosing a spot near the wall is safest. But, remember that people will be entering the water around all edges of a pool. It may be better to find a relatively isolated place, away from where people may be entering the water and away from large groups. Also, keep your distance from the pool drain, which can exert hundreds of pounds of suction and can cause injury and death.Have a friend keep an eye out for you while you’re below the surface. If you’re swimming underwater, keep an eye out for traffic and remember that other swimmers will not necessarily be looking out for you. Ideally you can chart a clear path ahead of you to the other side, one that will stay clear until you get there. If you're in the shallow side of the pool, you will likely be standing. If you're in a part of the pool where the water is higher than you are tall, your body will assume a vertical position with ease as, generally, your lower body will be heavier than your upper body. Do not hyperventilate. Taking several fast breaths in a row before submerging yourself is known as DUBB, "dangerous underwater breath-holding behaviors" and can cause hypoxic blackout, which can lead to brain damage, fainting, and death. Pull your knees in and hold them close to your chest by wrapping your arms around them. This tucked position changes the amount of space you're taking up in the water and will allow you to fall deeper into the water and to more easily remain underwater. Objects, and bodies, sink in water if they have a higher density...