In the grand scheme of things, you’re not meant to think about fashion too much in this country. Not if you’re to maintain any semblance of being a serious person. You’re meant to deploy your little grey cells on more pressing matters – the state of the planet, the state of the economy…

The thing is, if you’re remotely interested in clothes, all roads eventually lead back to the mecca that is fashion – or so I find. One minute you’re thinking about John Maynard Keynes or bankers’ bonuses, the next you find yourself wondering about the impact this will have on the nation’s swankier emporia and whether the Harvey Nicks sale has started yet, every cloud having a silver lining and all that. “Only connect,” wrote E. M. Forster. And I do.

Sometimes, this constant, if occasionally flickering, connection is a good thing. And this is one of those times. Because, if you’re constantly plugged into the fashion ether, you will have determined months ago precisely what is required to update your wardrobe. But does a wardrobe need updating in these challenging times, you cry? Is it even seemly to entertain such a notion? Not a bad question, considering that even those in the front rows at the shows keep confiding that they’ve stopped spending – “except for these Vuitton Tribal shoes/this Prada jacket/the Balmain dress/some Balenciaga trousers”.

Actually, the way many fashion industry professionals shop is quite sensible, within the context of what they do (ie, need to look fabulous all the time): they buy one big-ticket item each season, wear it to death and move on. This presupposes that they have all the basics covered, which of course, they do. There are only so many trench coats, black trousers, T-shirts, pencil skirts and flat sandals one wardrobe needs. After that, it’s about tracking down the one Major Piece (or, if you’re feeling self-indulgent, two, three or even four) that makes everything “pop”.

If you don’t have the basics, acquire those first – they’ll last three years, maybe longer. After all, the constituents of the perfect trench don’t change every season – the slim-fitting, neat-shouldered, sharp paradigm that looked so fabulous five years ago still looks terrific now.

As for a pencil skirt – the clue’s in the name. Ballet pumps are slightly different in that, while the raw ingredients are the same, the garnish is constantly updated. While prices for the designer versions seem steep for a flattie, cost per wear, they’ll pay for themselves. It’s also worth paying extra for embellishment that won’t drop off, which isn’t a very luxe look.

As for the “now” items to add zest to the basics, take your pick from the following: a corset top that will look amazing under a jacket but also work on its own at night or on a hot day (look for one that fits well and comes in cute rather than vampy fabric); a block-colour dress (the Times fashion team has gone mad for Richard Nicoll’s fuchsia, orange and flesh-pink ones); oversized sunglasses – a quick and easy statement, even though, in years to come, we’ll look back at photos of ourselves and wonder what we were thinking. It’s worth forking out for a pair that are solidly built and provide maximum sun protection, as this is one fashion item that should be fully functional, too. There is a similar argument for splashing out on an expensive pair of nautical trousers – they never go out of style, and expert cutting and a dense weave are vital.

As to what to hunt down on the high street, a denim jacket for sure, and a tulip skirt, which, along with the pencil skirt, is this summer’s shape. If you can find a chain-store version in a fabric you like, nab it, because they aren’t that hard to manufacture cheaply. Besides, while this style seems to be hanging on for next winter, who knows whether it will last another 12 months?

Large totes are always a good investment buy, which is an argument for investing in a quality one; on the other hand, if you’re easily bored, ransack the high street. One of my favourites is the stripey linen tote I got last year from Gap for £20, which was folded up for holiday packing, dragged to the beach and washed repeatedly and is still going strong.

Finally, coloured watches, as pioneered by Dior and Chanel, are a fun way to update your accessories. ToyWatch makes the ones to have, but, at £125 upwards, they’re a commitment buy. If you’re looking for a one-summer hit, head instead to www.asos.com for its own-brand pink or sky-blue timepieces, £19.95.

OK. I’ve done the thinking for you. Now you get back to John Maynard Keynes.

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