Come on in, the water's fine. New divers practice beach entries in calm conditions before tackling bigger surf.

In California, divers hit the surf about as often as surfers do. Diving from the beach has been an integral part of the California scuba experience since the '50s, when America first saw Mike Nelson run down the Santa Monica beach, throw a balsa-wood "tank" over his head and dive in to rescue a maiden in peril. Even today, most California divers complete their certification on beach dives, so handling the surf is just part of the learning curve.

Ask Cory and Jeremy Reddell. I ran into the boys (aged 14 and 15) at Biltmore Beach, Santa Barbara, where they were finishing their certification class. Bob Reddell, a proud father if ever there was one, watched and looked forward to the beach dives he'll soon be making with his sons.

They live within driving distance of several great diving beaches, and because it costs little more than the price of air fills (a dive boat would cost about $100 each), the three can afford to dive often. Other beach divers like the freedom. "You can pick your own site, as uncrowded as you want it to be," says Michael Adams, 32, of Thousand Oaks. And for multitasking divers, you can't beat the convenience of shore diving on your schedule, not a dive boat's. "I can dive in the morning and then make it to work," says Monica Hamblin, 25, of Camarillo.

Surf's Up!

Of course, there's that tricky surf problem. By far the most intimidating part of beach diving is getting through the surf zone. That's the area between where the wave first breaks and where the roller degenerates into confused white water rushing up the beach. Before you get out to the rollers, you can generally stand easily in the white water. Once you're outside the break, you can float comfortably because the water is moving only vertically, not horizontally, toward the beach. But in between those two areas, a breaking, rolling wave can overpower the strongest diver.

How do you get through the surf zone?

Timing is everything. You probably know about sets and lulls: Sets are groups of bigger waves and are always followed by lulls, groups of smaller ones. You know you're supposed to wait for the lull before going out, but you may not know the secret to timing it.

Here's a common rookie mistake: You watch one big wave after another pound the beach until the next wave seems to be a smaller one. "Is this the lull?" you ask. A couple more small waves follow. "Sure looks like it," you think. Then comes another wave, still small, but a little bigger than the last. "It's the lull, but I'm losing it! I have to go now!" So you stumble out, just in time to meet the returning set of big waves.

Decide at the outset, "I will not go out on the first lull I see no matter how easy it looks. I'll wait for the second or third." Or fifth or 10th if you have to. By standing and watching for a few minutes, you'll get a better idea of what the lull looks like that day. You'll also have a chance to relax a little.

That's when to go into the surf. What about how?

Shore diving is such an integral part of the California scuba scene that most open-water classes are completed on the beach.

Fins On? Fins Off?

There are two ways of getting through the surf. One method, the one usually stressed in certification courses, is to put your fins on at the edge of the water and shuffle backwards or sideways as far out as you can, then swim under the breaker. The other is to carry your fins in your hand, walk on your feet past the surf zone, and then put on fins. Both methods have advantages and disadvantages, and neither is best for every diver, every beach and every day. Experienced beach divers use both methods at times.

The "fins on" method has a lot to recommend it. When you fall down with fins on, you have propulsion. With any luck, you can swim through or under the waves and power past the surf zone. The problem with it is that walking through the water in fins is slow and unsteady. You can most likely forget about waiting for the lull because it will be over before you've gone far. You'll probably fall down and won't be able to get up again. You're also more apt to trip or slip on rocks just past the shoreline where it may be too shallow to swim.

On the other hand, if you walk out carrying your fins, you can go much faster, so you spend less time in the surf zone and, with luck, get past it before the lull is over. On your feet, you're much better able to sidestep rocks and retain your balance, to advance or retreat quickly if you need to. If you fall, you probably can get up again. Bill Kendig, 41, of Ventura, puts it succinctly: "Walking works best with feet."

Kendig, a California beach diver since 1975, is also a NAUI and PADI instructor and can appreciate both methods. "Which is best depends a lot on the kind of beach. If it's a gradually sloping beach and slow surf, it's easier to walk until you're waist deep and put your fins on there. If it's steep and the surf is big, you're better off having all your gear in place first."

As Kendig implies, a steep beach usually means a "shore break," where the wave breaks almost directly onto the sand. The surf zone is shorter on a steep beach, so your chance of getting through it on a lull is better, but the waves are probably bigger and more violent, too.

Bodysurfing or board-surfing experience helps you decide how best to approach the surf. "I learned a lot about beach diving from being a boogie boarder and bodysurfer," says diver Michael Adams. "I don't mind being in the surf. I feel comfortable with it."

If you're not comfortable going into the surf, Kendig has a suggestion: Go out first with no dive gear, just your wetsuit, to learn where the surf zone is and what the wave action is like. Next, add mask, fins and snorkel only, and try to go out through the surf. "If you can go out easily with mask, fins, snorkel and wetsuit, you can do it with your scuba gear," says Kendig. "And if you're having difficulty, that's a good time to say, 'Hey, forget it,' and not do the beach dive."

One last tip: When a big wave bears down on you, try to go under it, not through it. That means going out with little or no air in your BC.

That Two-Letter Word

Fins on or fins off? It depends on the conditions.

It can be hard to say "no" to the dive when you're standing at the water's edge, your buddy is flexing his pecs and you've already hauled all that gear to the beach. But, as Kendig says, "People get hurt because they try to force what they want to do on the conditions." In fact, among the divers I've talked to, it's those with the most beach dive experience who are quickest to call off a dive if surf conditions look doubtful.

"If everyone in the group feels comfortable, we go, but if anyone is hesitant, we call if off and grab breakfast," says DeeLee Bersbach, 26, of Thousand Oaks.

Monica Hamblin remembers one dive she and a buddy attempted even though conditions were less than ideal. After being beaten up by the surf, getting tangled in the kelp and discovering zero vis, they had to abort. "And then we had to wash our gear," she recalls.

Two tricks make it easier to say no. First, leave your heavy gear in the car when you make the predive recon in wetsuit only. If conditions look good, return to the car, put on the rest of your gear and go. If they don't, you haven't wasted so much effort. And second, have a backup plan so you don't feel you have to dive because your alternative is a wasted day. Have in mind another site. West-facing beaches are often calm when south-facing ones catch the swell, for example. And if all else fails, remember you're going to the beach. Can that be so bad? "So many times we've had more fun just bodysurfing on those days it's too big to dive," says Kendig.

Surf Exits

Returning to the beach can be more, uh, exciting than going out. The surf may have gotten bigger while you were on the bottom, and even if it hasn't, waves are always harder to judge from the ocean side. Once again, timing is key, and that requires the patience to wait for the right moment. Approach the beach until you're just outside the surf zone, put some air in your BC and rest there while you wait.

While you're regrouping, watch where the waves break. You want to get as close to the break as you can without being carried over the top, but be careful: Bigger waves break farther out. Watch where the waves go up the beach and move sideways to the best starting position. You want to be carried onto sand, not onto rocks or kids with inner tubes. Spend some time watching the sets and lulls, and find their rhythm. You're looking for the moment at the beginning of a lull when a wave is just passing under you.

At this point, there are several methods for getting onto dry sand. If the waves aren't too big, you can, as Kendig puts it, "kick like hell until you're in chest-deep water, then rip off your fins and run like hell." But be careful: Waves are almost always bigger than they look from the outside. If they look too big to outrun, another method is to deflate your BC and swim in on the bottom. You'll find very little turbulence only a foot or so below the rollers. When you get into water too shallow to swim, don't try to stand up in your fins; instead, crawl out on your hands and knees like a toddler.

And if the surf has become really big, try this: Outside the break, take off your tank and BC and inflate the BC. Take off your weight belt and strap it around the tank, through the BC's armholes. Tuck the hoses under the belt. Push the whole thing ahead of you toward the beach, using it like a boogie board. If you're separated from your tank and BC in the surf, push them ahead and away from you. You'll both end up on the beach, but the heavy scuba equipment won't be on top of you. Wearing only your mask, fins and wetsuit, you'll be able to ride the wave easily.

On the Beach

Of course, huge surf days are the exception, not the rule, at California's popular beach dive sites. More often, it's one of those gentle, sunny days that provide perhaps the best reason for beach diving: It's easily a social or family event. Maybe grandma watches the kids make sand castles while mom and dad dive, then everybody picnics on the beach. Maybe your surface interval means digging your toes in the sand and reading a fat novel or listening to a Dodgers game. Or maybe it's a long, quiet walk on the beach. Choose a site with a campground and complete the postcard picture by grilling the day's catch over the campfire, watching the sunset, then crawling into your tent or camper to avoid the drive home. Or better still: Suit up for a night dive.

10 Tips for Better Beach Diving

> To keep sand out of your wetsuit, your reg, etc., gear up at the car and walk straight to the water without stopping. Bring a tarp to stand on behind your car and a plastic tub to dump your gear in after the dive.

> Take several jugs of rinse water. They'll get warm in the trunk of your car.

> To change clothes in public, one option is the Changing Room, a mini-tent (www.gochange.com). Another is a huge caftan or bathrobe. But most divers work with a big towel and a car door.

> Keep gauges clipped in and use an octo holder.

> If you get knocked down by a wave, don't try to get up--especially with fins on. Just crawl on all fours, or swim.

> Once past the surf, swim out on your back. Look at a fixed point on the beach to see if a current is carrying you down the beach. If you need to reach a specific point like a buoy, take a compass bearing from the beach and use the reciprocal.

> Take a sharp knife or shears. There's more fishing line near shore and in kelp beds.

> Be aware that surf and incoming tides usually mean poor visibility. Vis usually improves farther from shore.

> To find the best entry points, ask lifeguards. Many are surfers or divers.

> Have an emergency plan: Where's the pay phone or cell phone? Who do you call? Where's the oxygen? Tell someone where you will be.