Big moment, then — the first job interview. You must get it right. It’s one of those moments when the language of dress speaks volumes. What you should aim for is something that conveys competence and yet a certain sophistication, that implies that you’ll be able to handle anything they throw at you. Too girly is inappropriate. Too dull is a waste of an outfit — and nobody wants to work with dull people, in my experience. If you decide to go for the sort of trouser suit that Armani devised specifically for these occasions, you should choose one that has a slightly curvy jacket or — better still, a flattering flounce at the waistline. Dress it up with ropes of pearls. And that sort of suit, paired with killer heels, goes happily to theatres, dinners and parties too.

If the interview is soon and you want something warm and wintry, you’d better hurry. Matches of 60-64 Ledbury Road, London W11 (020-7221 0255), and Browns, of South Molton Street, London W1, both have some terrific things still left in the sale: a fantastic Missoni jacket for £450 (down from over £1,000) at Matches; some delicious Marc Jacobs jackets at Browns. Either jacket could be teamed with black trousers or a slim black skirt.

However, for the coming season (spring/summer) most of the designers have done some gorgeous coats, that are pretty enough to pass as dresses and yet are useful cover-ups for when there’s a bit of chill in the air. Marni has a great way with coats and Betty Jackson has a particularly covetable number in a limey yellow but she also has them in bronzy brown and white — all delectable with lovely collars and huge buttons. To me, 5ft 4in and a size 10 sounds slim so you could, if you fancy it, go for one of the numerous versions of trench coats that are around.

Personally, I think you need to be very slim to broach the “belt around the middle” look on a coat but if you can, everybody from Prada to Burberry Prorsum has done a version and it’s the kind of coat which, if it suits you, will go on looking good for ever.

Fenwick is always a good shop for the working woman to trawl. There’ll be lots more coats later but for the moment there’s Max & Co’s pretty “soft” trench in pale sand (£210), which has just a half-belt at the back — easier to wear than the belt around the middle — and some fullness.

I think it’s worth investing a lot in one great jacket — then nobody looks at anything much else. It can then be teamed with simple black trousers and polo-neck sweaters, with skirts or shirts. You can get them in every price bracket.

It’s hard to beat Betty Jackson’s jacket in the tart, lemony colour sketched here by David Downton with a white tulip-shaped skirt. Zara has some good ones at about £80 a throw. Marks & Spencer has a very nice one in black with a red rose print (£75) but don’t make the mistake of teaming it with the matching skirt — wear it with a plain black skirt or trousers.

L. K. Bennett has a lot of good jackets and I rather like the one in green, which could be worn with lots of things that you probably already own, as well as with L. K. Bennett’s own green and white flowered skirt, come the summer. It comes in a pink version too. But remember that at job interviews hair, shoes and handbag are all a matter of some importance.

As a corporate bigwig once told me: “If I see someone looking scruffy, as if they don’t care about their hair or nails, I ask myself, ‘What else don’t they care about?’ ”

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