Nothing is more tragic than a preventable accident made worse by lazy, apathetic parents.

If you take on the awesome responsibility of caring for a child—even for a day or an hour—I believe there are four skills you should absolutely know how to do well, and without panic.

You should know how to swim. Children should never be out of sight near a pool, a lake or an ocean. Not for a second.

Obviously being in the water with them is the best option, but if you are only standing on the deck or shore watching, don’t you think it would be helpful if you—the person who will helping them when they get into trouble—is confident in the water? That means you know how to keep yourself afloat, move through the water, and drag someone along to safety. It’s a lot to ask, but if you can’t do it, you are absolutely useless to the child who is swimming.

If you don’t know how to swim, keep your kids away from water until you find someone who does, and they are willing to be responsible for your children. Tragedy only takes a second. Read this great blog post on the realities of drowning.

(And while we’re talking about it, a reminder that babies and toddlers need your full, undivided attention around tubs, buckets and puddles, too.)

You should know how to put out a fire. Learn how to use a fire extinguisher. There are different types of fires, and you should know the difference between them and how they react. Small fires become big fires very, very quickly. Freaking out isn’t going to help, and doing the wrong thing can have tragic consequences. Learn to respect fire—campfires, candles, gas stoves, torches, etc…—and how to extinguish them properly. If you get scared or flustered around fire, an incident while looking after children is a bad time to be forced to learn.

Note: Your first instinct must be to get everyone out and call 911 (or your local emergency number). Don’t hesitate.

You should know how to do the Heimlich Maneuver. Choking is common. Children regularly eat too fast, put weird things in their mouths, or simply make a mistake which can block their airway. Clearing a blocked airway is the first step in lifesaving. It’s a simple procedure and, done correctly, takes only a few seconds. Which is good, because when someone can’t breathe, you only have a moment to help.

You should know how to do CPR. Of all of these skills, this is the truly lifesaving skill. All the others are minimizing risk. If you’re required to perform CPR, you are sustaining the most basic life function, and keeping them alive until medical attention is available. Learn how to perform CPR on both adults and children (they’re different). It’s not hard, but you have to know what you’re doing. There are good classes available almost everywhere.

I am strong advocate of everyone learning (and practicing the skills of) basic First Aid. When someone is hurt, managing injuries is critical. Sometimes, just understanding simple care can mean the difference between a painful lesson and a horrible outcome. Beyond cuts and bruises, take the time to learn about managing trauma, or helping when someone is terribly sick. Confidence and composure in an intense situation—and just a little knowledge—will only improve the outcome.

Unfortunately, in life there is rarely a lifeguard on duty.