Never swim alone.
Don't swim if you've been drinking alcohol.
Swim only in guarded areas. Almost all of the drowning at Grand Strand beaches in recent years have happened when the lifeguards were off duty.
Watch children carefully when they get in the ocean.
If you get caught by an undertow, the pull of a wave as it pulls back from the shore, don't panic or try to fight it. The undertow may pull you out toward the sea, but it will stop eventually. You'll be able to come in, or you can tread water or float until someone can come get you. Some days the undertow is worse than others. One rule of thumb is the bigger the waves, the stronger the undertow. When you first step in the shore break, notice how strong the undertow is before you go out. If the undertow is especially bad, stay in shallower water.
If you get caught in a riptide, the pull of a wave between sand bars, don't panic. React the same as you would to an undertow. You may choose to swim parallel to the shore until you swim out of the riptide. Then, head for shore.
Before you jump in, check with the lifeguard about ocean conditions. Lifeguards fly flags that tell you at a glance what to expect; kinda like traffic signals for the ocean. As you might expect, a green flag means "go ahead." A yellow flag means you'll need to use extra caution while swimming. And a red flag... NO SWIMMING.
Jellyfish stings usually aren't serious and amount to little more than brief discomfort. If you get stung, there are two health tips you need to remember _ don't rub it, and don't put fresh water on it. Some old home remedies you might want to try include sprinkling a little meat tenderizer on the afflicted area, dabbing it with diluted ammonia, putting a poultice of tobacco on it, covering it with Crest toothpaste or a mix of toothpaste and baking soda. Most lifeguards are armed with an aerosol spray that takes the sting out quickly. If a tentacle has come loose from the sea creature, it can still sting you. If a tentacle wraps around a part of your body, don't try to pull it off. Grab a shell, comb or other device and try to lift it off.