To minimize the risk of decompression sickness while diving:
Dive and rise slowly in the water, and don't stay at your deepest depth longer than recommended. Scuba divers typically use dive tables that show how long you can remain at a given depth.
Do not fly within 24 hours after diving.
Don't drink alcohol before diving.
Avoid hot tubs, saunas or hot baths after diving.
Make sure you are well hydrated, well rested and prepared before you scuba dive. If you recently had a serious illness, injury or surgery, talk to your doctor before diving.
Some people should avoid diving altogether, or should consider special risks. If you have a heart defect, it is not safe to dive. If you have asthma, a history of a ruptured lung at any time in your life or another lung disease, discuss diving safety with a doctor before deciding whether to dive. A person who requires insulin to treat diabetes may have wide swings in blood glucose levels during a dive, and caution is advised. Avoid diving if you have a groin hernia that has not been repaired, since expanding gas in the hernia can cause symptoms.