1. Prepare for breathing: take a deep breath and breathe fully, so that each breath reaches 70-80% of vital capacity. Exhale as completely as possible to eliminate lung waste gas. This can prolong the time under water.
2. Keep your body balanced: When entering the water, hold your body with your hands and feet to keep your body balanced, then stretch your limbs and start paddling. You can't swim with strength until you have a good balance.
3, hand movements: the elbow is always close to the body, the thumb enters the water first, and the palm is pulled out. When paddling, put your hands gently on the surface of the water and don't go too deep into the water.
4, foot movements: foot movements should be light, toes should be watered first instead of heels. Legs should not be too straight, but they should be bent to some extent. When paddling, you should exert your strength from your hips to make your feet sweep an arc on the water.
5, breathing coordination: hold your breath when diving, according to physical fitness, you can stay underwater 15-90 seconds. Inhale immediately after coming out of the water, and then start breathing regularly. Breathing should be carried out regularly with the rhythm of paddling, generally 3-5 paddling is one breath.
6. Protect your ears: Due to the water pressure, it is easy to let water enter your ears when diving. You should make waterproof plugs or put on earplugs in advance to prevent water from entering your ears. After coming out of the water, tilt your head to drain the water from your ears.
7. Keep the direction of your head: In order to observe the underwater scenery and environment, you should always turn your head, but turn your eyes and try not to turn your body. The body should always keep the original direction of movement.
Diving and swimming also need to pay attention to the following safety matters
1. Choose a suitable water area: seawater is more suitable for diving than lake water or river water, and the place with clear water quality is better. The area with water depth of 5- 10 meter is relatively safe, and the water flow should not be too fast. Try to avoid obstacles in the water.
2. Check the equipment status: check whether the oxygen cylinder, face mirror, breathing tube and other equipment are unblocked and sealed to prevent air leakage or water ingress.
3. Underwater sense of direction: keep a clear sense of direction underwater, know the direction of the last boat, and avoid getting lost. It would be better if you could carry an underwater compass.
4. Master all kinds of gestures: When diving with other divers, you should be able to communicate with some simple gestures, such as "Everything is OK", "Floating", "Separate Action" and "Distress" to cope with unexpected situations.