Washington is an artificial city, shaped like a badly flawed diamond and surrounded on all sides by America.

After every election, a new crop of American immigrants comes to the city, which they have been taught to call Our Nation's Capital, and most of them go home as fast as they possibly can.

Why is this?

The answer is simple. What they are expecting is a somewhat larger Cincinnati, and what they are finding is Singapore.

For Washington is essentially an Asiatic city, a city of castes and face, of immense unearned wealth and poverty, of Oriental indifference and offhand miracles, of people living and dying in the streets of bottled genies, of fakirs and sacred cows and magic carpets and grand viziers. We even eat ghee. We call it French cuisine and pay a lot for it.

Here is a brief guide for those Americans who would like to become Washingtonians. It is woefully incomplete. (So Asiatic, this advance modestly.)

Driving: Always count to 10 before starting up when the light turns green.

If you see a green light 100 feet ahead, slow down immediately because it might turn yellow. If the light is red, drive right on through. You're not gonna let some damn light bulb push you around.

About your car: Have a telephone, but never in the front seat. It must be in the back seat, and you must have a little reading lamp on the back shelf. bThis means you are going to need a chauffeur. Excuse me, driver. Only diplomats have chauffeurs (also tiny flags on the fenders; you should not have a tiny flag on your fender, or even an empty flag bracket; we haven't done brackets since the Nixon days).

A driver is anyone you can talk into wearing a black visored cap. Your husband could help out if he's a good guy.

Clothes: For women, wear what you would wear to your aged aunt's funeral. For men, suits. Always suits. Absolutely nobody wears slacks and jacket except newspaper reporters who had planned to spend the day comfortably at the desk and had to borrow the office jacket for the assignment. cSweaters are worn only by street vendors and senior senators. (We had a president once who tried it, but the guards wouldn't let him back into the White House for two hours.)

And, oh yes, it you are a woman who was an executive assistant in your previous life, do not continue to wear your cashmere cardigan cape-fashion with the top button buttoned. Don't ask why.

Colors: November through March, we all wear navy blue, with thin white vertical stripes like negatives of the Devils Island uniform. July through September it's those tan tropicals. You have to own two because they water-spot. (Profoundly Oriental, this. Like having six-inch fingernails.)

The rest of the year we wear gray. With vest, for men. With pleats, for women. Men do not wear skirts ever. You will sometimes see a man wearing a kilt, but he is always careful to have the whole costume, down to the sporran and the knife in the sock. The average Washington man would rather be mistaken for a Scot than for a woman.Similarly, women may never wear pantsuits. Not ever. Not even for a gag.

Parties: Seem to drink. You can eat all you want. Do not have a very good time. Laughter is for out-of-town relatives.

If there are important people at the party (and there always are: Importance expands in a vacuum), don't, for heaven's sake, hang around expecting to hear policy decisions being hammered out. That business about history being made at Washington parties is a myth. The real discusions are made in cars.

"You need a ride home?" the congressman says to the media executive as they leave. Naturally the media executive does, even though it means he or she will have to come back for the car after. They drive off together, and the fate of nations hangs on their conversation.

By the way, you should leave at the same time. You ought to know that Washington has a caste of professional party-closers. These people attend every official party and reception, and their function is to stay on until the caterers begin to remove the liquor bottles. Since the real guests drink so little (with notable exceptions), and the host would lose face if his garbage cans weren't stacked with empties that next morning, this caste performs a valuable service in Washington society.

But they are untouchable, and it is not considered polite to interfere with their work.

Status symbols: The status symbol in Washington is not to have a status symbol. If you receive an invitation to a White House dinner, do not prop it up on the mantlepiece. You are merely leaving yourself open to something like, "Oh. You're on the Tuesday list. Huh." Do not quote George Will or Stanley Karnow. Do not even mention Evans or Novak. They are probably standing behind you. If not them, their editor. If not their editor, then a close friend.

Now, this close friend is someone you need to know about, who belongs to a very refined caste, the local samurai. It is the Old Washington Hand caste, which believes itself to be an elite but in fact is rather like the Mayflower descendants, for every American who comes to Washington to live or even to visit claims to know at least one Old Washington Hand.

You will know this caste at sight. They look tired. In point of fact, they are tired. They are people who, as we say here, Peaked Too Soon. You too, if you stick around after losing your job in one of our dynastic upheavals, can become an Old Washington Hand.

Politics: Do not try to talk politics to a Washingtonian. We don't know a thing about politics. If it had been up to us, we would have elected McGovern in a landslide in '72. And look what happened this time. All we know for sure is that Republicans rent and Democrats buy.

Weather: It is hot here. We have winters, indeed sometimes several feet of snow. We import frozen winds from Manitoba and hurricanes from Louisiana. We can ice over the Potomac to enliven your elevator conversations, and maroon hundreds in their offices when the going-home traffic panics at a half-inch blizzard. But basically, Washington is hot. It is hot. Bus riders melt before your eyes while sitting perfectly still by an open window. The white lines on the pavement swoon and go all wiggly. Bank managers take off their shoes and wade in the foundations. The squirrels pant.

Now, this is to be expected. Everyone knows that politicians love heat. We have had national conventions in Miami, Los Angeles, San Francisco, Philadelphia . . . How many have we had in Anchorage?

You go down the street when the temperature is in the high 90s and the sky is a fuzzy yellow Hudson Bay blanket about 30 feet in the air and everywhere you look collars are flopping sadly on collarbones, and suddenly you spot one person, smiling and blithe, crisp-shirted, dry-foreheaded, striding along, looking serious -- well, that person is a politician. I guarantee you.

Why don't presidents wear hats? Think about it.

Vacations: Go Directly to Martha's Vineyard. Do Not Pass Rehoboth.

Do Not Talk to the Washington press people. They are on Nantucket anyway.

Lunch: This is another myth, like the history-making dinners. Meet somebody on the street, talk for two minutes and next thing you know it's "let's have lunch!"

The delusion is that you two will get together and influence each other. What actually happens is that you find you are expected to choose the place ("it's your turf, old pal . . ."), but you always eat at disgusting little sandwich bars, so instead you both venture into a posh, expense-account spot where you have to wait in line. Before you're even seated, you've run out of dialogue.

If you do have a neat hideaway where you are known (but not so well that they set out your martini unasked), then you are One-Up. There is only one way to parry this: In the same tolerant tone in which you would say that you don't watch cartoons on TV, simply mutter: "I don't eat lunch."

What to read: Skip all the news magazines. Don't bother with the local papers or even The Times. Read something nobody else reads. The London Daily Sketch. The Trinidad and Tobago Evening News. The Biafra Sun. Cuba's granma. Read every word of it and memorize ever mendacious statistic.

Regularly work these statistics into the conversation at any cost. We love statistics in Washington. We use them the way a deer poacher uses a blinding light.

So. Now you understand Washington. Maybe now you will stay longer than two years. If not, be comforted. Others go before you.

As the philosopher said, if you can't stand the Tempest, get out of the Teapot.