Cameras have become everyman's playtoy. Only transistor radios and Coca-Cola are more ubiquitous on the planet. But some people think inspiring photography requires long-planned trips into the wonders of nature, or years of experimenting with complex indoor lighting. Not so. The very best subjects of all -- children -- are usually so handy as to be overlooked.

Regardless of your photographic aspirations, there is not a parent on earth who does not want to record the wobbles, stumbles and wonders of their children growing up. Everybody takes snaps, but not many people take pictures. There are a few simple rules that will give special life and laughs to the pictures you make of the little people in your life. GET DOWN -- You photograph adults at eye level, so do the same thing with kids. Shooting down is the single most common mistake in child photography.

You have to be willing to bend your knees, scuff your shins and even grovel around on your stomach (as Id did over Christmas) to capture the special joy in children's eyes and faces. When they're playing on the floor, you should lie down, put the game they are playing into the bottom of your frame and shoot up into their laughs.

At tables, use the tabletop to rest your camera hand on -- being careful of vibrations -- to produce a picture that truly shows a kid's-eye view of dinner as seen by a four-year old. The table becomes wide and distant, the food small mountains. SHOOT DOWN -- There's one exception to the first rule: This involves shooting down at a child from almost directly overhead. This emphasizes the smallness of the young one and shows how high up he must constantly gaze to make contact with the adult world around him. The only problem with this method is getting your own feet into the picture. KEEP BACKGROUNDS SIMPLE -- Two of the best backgrounds for portraits or even full-length shots are grass and the sky. It's very easy, and very effective, to stoop down below the child's height and frame his face against the sky.

It's equally striking to shoot down at a child against an unblemished background of verdant lawn. Fortunately, broad greenswards are easily, found in the malls and parks around Washington.

Snow and sand make equally striking backgrounds but create glare problems except on overcast days, so read the light very carefully.

When you're saddled with a "busy" background you can't escape, look for open shade with a leafy background. Then try to unfocus the background by shooting at the widest possible aperture and fastest shutter speed -- say f/2.8 at 1/1000th of a second. Just make sure you focus carefully on the child. KEEP THE CAMERA HANDY AND SHOOT A LOT -- For reasons of cost, it's best to master child photography with black-and-white film before plunging into color. Buy film in quantity (you get discounts for 10 or 20 rolls) and always keep a camera loaded, like a hunter in the woods. The camera(s) must stay out of a child's harm's way, but be close enough for you to grap just when Johnny splashes chocolate cake all over his face. COMPRESS DISTANCE -- Remember that to a small child, the world that's unfolding is an awesome place. One way to capture the sense of exploration is to compress distances with a telephoto lens. I prefer a 105-mm for everyday use and a 200-mm for special effects. I once caught one of my sons standing, in diapers, in high weeds that rose almost to his shoulders, looking around in wonder.

Another time I saw both sons, Christopher and Shannon, emerging with their wagon -- one pushing, one pulling -- from a tall stand of straight Georgia pine. The picture from 50 feet made them look like cherubs leaving a primeval forest.

These are times, of course, when parts of the background can be important -- a visit to the Lincoln Memorial or a first bicycle ride, for example. Many parents think they must include the entire background to tell the story; no so. You can frame the heads of your children up close with the spike of the Washington monument rising over one of their shoulders -- that tells where you were that day without trying to include the entire 555 feet, 5 1/8 inches of stone in the picture. An anguished face framed by a slightly-out-of-focus set of handlebars says it all about the first bicycle ride. FOCUS CAREFULLY -- Too many people simply point the camera and shoot. For large prints that you may want to hang, sharp focus is critical. I focus on the light reflections in their eyes. On a sunny day outdoors, focusing on lips or ears may suffice.

Once you have mastered all the technical pointers, the real fun begins -- having a sense of the moments when good pictures are happening.

With practice, your eyes become trained to see through a rectangular frame even when you have no camera at your face. Two children playing in a lush growth of ivy ground cover; a child sprawled on the lawn talking to a pet; the struggles of getting long strands of spaghetti from plate to fork to mouth; the sudden clownery of a Halloween costume; the inimitable joys of opening Christmas presents.

Let photography become a casual hobby, rather than a planned event. Let the camera merge with such appurtenances of family life as coats, hats and footballs. You don't need to stage pictures of children; they invent more "photo opportunities" than you can possibly keep up with.

A psychological pointer: If you have a recalcitrant subject (some kids are natural hams, others extremely camera-shy), let the child take a few shots of you first. Then it becomes a game rather than a chore.

If you remember nothing else from this, please parctice one thing: get down! After all, they're only kids.