You are your own finest creation, says our design critic, Stephen Bayley. Here are his tips for making the best possible impression.

　　Stephen Bayley

　　The Observer, Sunday 4 March 2007

　　'You do,' someone once said, 'a very good impression of yourself.' Self-invented people are the most interesting ones of all. Believe me, I know. Technically, you and I are much the same: 96.2 per cent organic elements, including water, the proteins of RNA and DNA, lipids and sugars. Then there's oxygen, carbon, hydrogen, nitrogen, carbon dioxide, calcium, sulphur and traces of chromium, molybdenum, vanadium, tin and zinc. The difference is in the intangibles of the personality we create for ourselves.

　　John Osborne was a great self-invention. He said: 'I was born with a sense of loss, a feeling of things withheld and banished.' Osborne, acting to the end and even beyond, was buried in a Turnbull & Asser smoking jacket with a favourite edition of Hamlet with all the parts crossed out except the protagonist's. Splendid stuff.

　　It wasn't that bad for me. I grew up comfortable, but rootless, most psychologically at ease in the back of a car or in a restaurant. Actually, I am convinced my passion for modern architecture and design was based on a need to find substantial values in a shifting, temporarily Godless, universe. That was the beginning of my self-invention, but it is not just me. We are all at it. We are all works of art, or, perhaps more accurately, works of architecture with those three essential elements of core, frame and envelope. For the moment, I am most concerned with the envelope. As Machiavelli knew, appearances are real.

　　So it is important to understand how we make an impression. You give a first impression whether you want to or not, so best make it work for you.

　　Psychologists know that first impressions are based on our spontaneous assessment of status, clothes, sex, age, size and posture, speech and facial expression. Let's just deal with the clothes. Lord Chesterfield advised his son: 'Dress is a very foolish thing; and yet it is a very foolish thing for a man not to be well-dressed.' And Jay McInerney says of life today in meritocratic Manhattan: 'You won't be judged by your accent... but you will be judged by your shoes.'

　　This is nothing to do with Church's or with Prada but with attitude and style - style being the dress of thought, the feather that makes the arrow fly straight, not the feather you put in your cap. It matters because somebody who does not care about their appearance will care about little else. But we are locked in a game of continuous evaluation from which there is no escape to a value-free neutrality. Even the decision not to wear clothes betrays a set of prejudices. The person who says: 'I don't care what I wear, I just put on a T-shirt and jeans' is merely confirming how much he cares about creating a certain sort of wearily insouciant impression.

　　In matters of dress, you can be sympathetic to your audience, subvert it or confront it, but you should not ignore it. Kandinsky constructed his vivid and elaborate abstractions while wearing a tailored three-piece with a watch chain. His Bauhaus colleague Moholy-Nagy (while working on his life's project which he called 'the hygiene of the optical') wore a boiler suit to demonstrate technical credentials. I would dress differently for, say, a book launch, a date (even with my wife), a student lecture or a formal meeting where I was hoping to raise ￡5m from a Swiss bank. And it might not be exactly as you suspect: the flowered shirt with jeans for the bankers and the dark blue suit for the students would, I think, make the most interesting impression.

　　In all of this self-invention, confidence plays a part. The great thing about confidence is that it is self-perpetuating. Get a little and you will soon have some more. It's a cumulative process; as people respond positively, your confidence builds. Sometimes, the most unlikely people lack the confidence trick. The formidable Beatrice Webb said: 'If I ever felt inclined to be timid as I was going into a room full of people, I would say to myself, "You're the cleverest member of one of the cleverest families in the cleverest class in the cleverest nation in the world; why should you be frightened?"' Try this, I recommend it.

　　Disraeli is helpful here. His 'never complain and never explain' is well-known, but I particularly enjoy Elbert Hubbard's addendum: 'Your friends do not need it and your enemies will not believe you.' Anyway, being disliked can be a powerful stimulus to high performance.

　　But you do not have to be present to do effective self-invention - you can do it remotely, via the Post Office. In a man's letters, his soul is laid bare, so the craft of writing has a special significance in DIY design. In the early days of the mail, postage was paid by the receiver, but Rowland Hill's conceptual revolution made it payable by the sender. Thus the psychology of sending letters is significant. To write a letter is to show you have spent money, spent time and made an effort. I discovered very early on the power of the letter, a powerful tool in teenage courtship - more powerful still now that the majority of the post is garbage and any clown can generate something exquisite in Helvetica 14 point. The price of decent writing paper and a first-class stamp is one of the great bargains. A letter is an opportunity to write an advertisement for yourself.

　　I also discovered the power of postcards. First, they are amazingly cheap to make. I had an early period where I copied Expressionist woodcuts, matched them to depressing quotations in German and had them printed in the hundreds by the local copyshop. I have now matured to homilies from Ruskin printed in woodblock on handmade paper by a master typographer, but the principle is the same. Then there is the question of the correspondence itself. Four or five square inches requires real ingenuity to make sense or be funny. Writing sensibly on a postcard is an exercise in data compression, similar to - but more demanding than - text message. No one exhibits your texts for inspection on the mantelpiece. Postcards are a personal form of viral marketing.

　　If you are pitching yourself in a letter or a postcard, the handwriting assumes terrific significance. I developed an extravagant hand, loosely modelled on what I thought was an architectural style: black ink, italic, splashy, a weird combination of high visibility and low legibility, but it nonetheless impresses. I have often thought that hearing a woman say: 'You have beautiful handwriting' is one of the most seductive moments of all.

　　Indeed, a newspaper once sent my handwriting away for graphological analysis, a sort of psychological blind-tasting. The result came back: 'His presentation skills are off the chart, as is his creative thinking. He is opinionated, innovative and people-oriented. Blessed with the courage of his own convictions, he leans to extremes, black or white. Never grey. You simply can't ignore him. The word "bolshie" comes to mind.' This delighted me so much I have it as a header on my curriculum vitae (just in case anybody should ever ask for it).

　　A certain audacity in conversation, a reckless promiscuousness with reference, are other elements of the self-invention package. It is said the recipe for happiness is good health and a bad memory, but a good memory works better. I learnt that powerful recall and an ability to quote quotes and cite dates gave a persuasive simulacrum of high intelligence. I discovered at university that a certain lecturer's notes were taken verbatim from a standard work (I used to amuse chums by running my finger along the lines in synch at the back of the auditorium) and this taught me that very few people are truly in possession of the intellectual or academic authority they claim. This was an invitation to boldness. If you have the nerve to say it, something like, 'There's a charming little panel by Valdes Leal in the monastery at Elciego' has an impressive effect. There isn't, but who will refute you?

　　Stephen Potter advocated a similar device in the notoriously tricky area of wine snobbery. He recommended saying something completely meaningless, such as: 'This wine has great corners.' But the important thing is to say something interesting. There's a wonderful self-portrait by Salvator Rosa in London's National Gallery. It carries the inscription 'Aut tace aut loquere meliora silentio'. Shut up, or say something useful. They do a very nice postcard of it. I have used lots.

　　Of course, there are dangers in designing your own personality. Marcel Proust and Cary Grant had a lot in common besides fastidious taste in clothes. Each knew that the most dangerous sort of plagiarism was self-plagiarism. Grant perfected a screen persona of dazzling suavity and effortless cool. Hauntingly, he once said: 'Everybody wants to be Cary Grant. Even I want to be Cary Grant.'

　　It is said that we are all three different people: the person we think we are (the one we have invented), the person other people think we are (the impression we make) and the person we think other people think we are (the one we fret about). You could say it would be a lifetime's quest to reconcile this battling trinity into a seamless whole. Maybe, but for the time being I am convinced that, in Kurt Vonnegut's words (there I go, quoting again): you are what you pretend to be.