Some women are blessed from birth with knowing exactly what looks good on them, and with bodies that just about anything looks good on. The rest of us -- most of us -- usually think of clothes in terms of what they will conceal .

We're seldom sure what looks good on us and when in doubt will buy navy blue. We're victims of those twin scourges: Imperfect bodies and Inadequate Fashion Sense.

Shopping for us presents moment after moment of Final Truth, acted out before full-length mirrors in the glare of greenish fluorescent lights. With the event so traumatic, so intimidating, it helps to take a friend, right?

Wrong. Most of us need all the encouragement we can get, and the world contains an alarming number of nay-sayers, some of whom appear as ordinary, even nice people -- until you get them in a dressing room. There, under the guise of friendship and helpfulness, they talk us out of everything we start to buy without our even noticing it.

It isn't until we get home and discover we're empty-handed, or worse, loaded down with clothes we'll never wear, that it hits us.

If you're out shopping and you suddenly realize that you're with one of the following kinds of people, stop, don't pass go, head directly for home. (It's okay, just say you remembered an appointment with Adolfo in the morning.)

The Fantasy Dasher does her work when we have something on that makes us want to leap onto a table with a rose in our teeth and dance the tarantella before a count with laughing eyes. Just as he's about to lean close and whisper, "I want your body," she bursts into our dream with the prosaic observation, "I knew of a call girl who had a purple fake fur coat like that," or "Punk rock has made sequined jeans so popular," or "All my daughter's friends just love those little camnisole tops. She's 9, you know."

She is, perhaps, a bit more subtle than the Putter Douner. Sometimes this one puts down literally, as in, "Down-filled coats make some women look like blimps, don't you think?" Or "My mother always swore that orange makes most women look pasty-faced," or "Funny how stripes make thin people look thinner." Sometimes she varies her salvos by pretending to put herself down. "I'd love to wear skimpy little blouses like that, but with by bosom . . ." or "There's just no selection in size 6, us poor little women just don't have the choice you lucky 18s have," or "Somehow I just never look right in those mannish suits, it's lucky you're so angular."

And then there is, of course, the Practical Economist who makes you feel guilty or foolish about every intended -- and duly rejected -- purchase. "But it isn't on sale! Come on, you can't spend that much; just wait, it's bound to be cheaper in a couple of months," or "The suede will come off on your coat, you know," or "But linen wrinkles," But wool has to be dry-cleaned," "But silk frays!"

She is in direct contrast to the High Stickler who exclaims with a shudder, "But that purse is vinyl!" or "You can really tell it's polyester, can't you?" Or "Let's see if they have it in crepe de Chine."

She is related to the Law and Order Sheriff who knows more fashion laws than you know names of garments. "You can't buy that dress, mauve's a winter color," or "But you can't wear T-straps with a floral!" or "Of course, the blouse absolutely demands button earrings."

The Noticer is the same kind of stickler, but in a different way. She sews. She'll lift the shirt of the dress you're thinking just might do, in fact may be feeling almost good about and say, "Wouldn't you know it, the inseams aren't pinked and they're less than 5/8 inches," or "But the facings aren't interlined!" or "Good grief, can you believe this, they didn't match the plaid at the seams."

The Color Artist has the same sort of passion for details, but in this case, it's about whether to match or contrast a skirt. This boils down to getting a blue sweater the same shade as the skirt or a taupe/chartreuse/salmon one. The color artist will say, You'll want your accessories in fuchsia to bring out that tone there," pointing to a speck of color under your left armpit. It was these color artists who once told redheads they couldn't wear reds or pinks.

The last one, the Fashion Pro, is not detailed in her standards, merely emphatic. She says with simple indisputability things like: "Impossible." "Passe." "Jejune." Most of us spineless ones react by affecting disgust and thrusting the offending garment from us.

Well, is there anyone we can safely take shopping with us? Yes, the Encourager. This welcome, wonderful person is the kind who makes us feel so terrific about oursleves that we feel gorgeous in everything and so confident that we can begin to rely on our own judgment. This just to be sure you recognize her, is the friend who says, "Gee, I wish I could wear dresses with the flair you go," or "That really shows off those long legs of yours," or "That sweater makes your eyes look wickedly green."

Okay, they might sound a little overdone here, but nothing in the compliment line is overdone when you're standing amidist intimidating piles of clothes in a dressing room whose mirrors reflect your image into infinity and have just noticed that a size 12 doesn't fit as it used to.

At that point the true Encourager says something like, "Did you see that man out there? You know he's a count, don't you? Well, he can't take his eyes off you and I just heard him ask the clerk, 'Who is that women with the size-14 body?'"