1. Just before going in the water, squirt a couple drops of anti-fog solution (dive shops often provide this) on the inside surface of your kids' mask lens, then rinse. This step helps keep the glass clear. In a pinch, kids can spit into their mask instead and rub the saliva around the glass. It sounds gross, but some divers swear by this method for keeping the glass clear -- and some kids might actually get a kick out of it.

2. Have your kids brush their hair away from their face before they put on their mask. You can rub a bit of petroleum jelly around the mask's rubber edge for a better seal.

3. Practice using the mask and snorkel while still on dry ground. It's simply a matter of breathing through the mouth. Your kids should get a feel for it pretty quickly.

4. Now they're ready to stand in calm, waist-deep water. Have them lower their heads to peek at what's under the surface while steadily breathing through the snorkel. Next, let them do some belly floating without fins. They can also try diving below the surface, holding their breath while the snorkel's top is underwater. Upon resurfacing, they should exhale in one big blast to purge the water from their snorkel before breathing again.

5. Once they're adept at floating and breathing, your kids will probably be clamoring for fins. In placid water or in a pool, it's easiest to sit down in a shallow place to put on the fins. If there are waves, have them sit on dry ground, pull on the fins, then walk backward into the water, looking over one shoulder.