The 1661 syndrome – whereby a woman (and it almost always is a woman) looks like a bouncy-tressed, pert-bottomed teenager from behind and a grandmother from the front – has become a cultural joke, in much the same way that dressing like a WAG has (ie, not everyone finds it funny). Some feel that to castigate women for trying to hold back the years is a subtle form of misogyny. Although as far as this charge goes, we should remember that for years men have been wearing toupées to try to camouflage their age – and we laugh at them, too. Perhaps it’s ageism, plain and simple.

The fact remains, however, that among their many virtues, clothes should make us look more attractive than we are naked, not less. Call me a blinkered reactionary, but I don’t think that a vest accessorised with bat wings and whatever those splodgy bits of fleshy hinterland that sprawl out beneath the straps and sides of vests are called will ever be the ideal first choice for women d’un certain âge. On another note, doesn’t wanting to look 20, 30 or 40 years younger than your actual age smack ever so slightly of skewed judgment, if not desperation? And what to make of those who dress far beyond their years?

This is constantly shifting territory. I’m not talking about overkohled 13-year-olds hell-bent on passing for 18 in the pub. ’Twas ever thus, and – rather sweetly – all that trowelled-on slap generally makes them look younger, as though they’d just come from an advanced face-painting class. I’m not referring to twentysomethings decked out like prim, Victorian housemaids either, or trussed-up like Miss Moneypenny – that’s usually a fashion statement, or meant to be ironic.

No, I’m talking about those who have turned their backs on fashion altogether – or at least about those who persist in catching fashion on its final curve, or even slightly after the curve has hit the horizon. It is as if one is just too careworn and past-it to delight in anything newfangled. This is ageing in itself: just as dressing too young for one’s years often entails flashing too much flesh, dressing too old often takes the form of an overstated demureness (see Katie Holmes’s journey to the heartlands of county style this past year).

Elsewhere, it can take the form of a precocious pile-up of iconic labels. Dressing too old for one’s years often entails, à la Catherine Zeta-Jones, persisting with old-fashioned notions of what constitutes glamour (everything just that little bit too shiny and manicured, and profoundly devoid of any fashion detailing that might not immediately appeal to middle-aged and elderly men).

Interestingly, while dressing too young is a quintessentially British trait (the don’t-care-what-I-look-like approach), dressing too old (the caring-far-too-much stance) tends to be more common among Americans – which is rather ironic, given how much they spend on plastic surgery. One of the great glories of youth is that it shouldn’t look as though it’s trying too hard at anything. It certainly shouldn’t be slipping those so-called invisible shoe socks inside its ballet pumps to prevent rubbing.

At least the advantage of dressing beyond your years is that eventually it catches up with your taste. Dressing too young, on the other hand, always becomes pathetic.

Much comes down to personality, deportment and a combination of attitude and, let’s face it, accessories (Reese Witherspoon in retro 1950s, with her perfect blonde Peggy Sue hair and make-up, looks mature beyond her years, Lily Allen in retro 1950s, with her plastic jewellery, plimsolls and ragga-girl hair, looks cute). Should Jo Wood, the fifty-something wife of Rolling Stone Ronnie, stop dressing like a rock chick? I would argue not, since she is, after all, one of the original rock chicks. The look suits her. It’s an expression of who she is – and it’s not as though she’s so wrapped up in the illusion of how she used to look that she’s had lots of surgery.

So what am I saying? That dressing your age is as individual and nuanced as your DNA? Partly. But I also believe that there are useful guidelines to be made for those who want them – which should be all of us. If fashion is about anything, it’s about cultural adaptability. Not dressing your age means not only that you’ve slightly lost sight of what to tune in to, but of who you are.

Going grey gracefully

For many women in their fifties and sixties, hair colour becomes a thorny issue, especially for those born with dark tresses. The two traditional options are to go blonde, as if one shade suited all, or to continue pouring on the dark dye, both of which can make you look like mutton dressed as lamb. Skin tones change as we age – just because you’re naturally raven-haired doesn’t mean that the colour still suits you. Of the above two, finding a shade of blonde that suits is probably the safest option, but there is a more radical, potentially more interesting, option: go with the grey.

“It’s a choice that women are going for increasingly,” says Ian Black, the technical director at the Aveda Institute in London. “Well maintained and cut in a modern style, grey can look incredibly classy and elegant. And because you’re not putting lots of chemicals on the hair, you can really focus on its condition and shine.”

Dressing too young

— Skimpy jeans: the body may be able to take it, but can your nearest and dearest? Jeans are fine, whale-tails are not. Rethink the waistband.

— Camisoles: even under jackets these look bad after a certain age. Choose tops with wide straps or short sleeves instead of spaghetti straps. Go for flattering (and fluttery) short sleeves that cover the tops of the arms.

— Long, straight hair: you’re not Jean Shrimpton.

— Raven hair: just about works on 20-year-old Goths; hideously ageing on anyone else. Brunette is better and, after a certain point, grey is, too.

— Minis: a fortysomething with terrific legs can do them (see Elle Macpherson), but the pins really must be flawless.

— Directional shoes: these might seem an instant updater, but they’re undignified. Conversely, clinging to the styles of yesteryear (that includes kitten heels) is also a bad idea.

— Bare midriffs: no, no, no! Even if you do practise yoga every day. Baring your shoulders, back and collarbone is much more sophisticated.

Dressing too old

— Too much fabric: pussycat bows with jackets and knee length skirts à la Katie Holmes – this is not the era of Margaret Thatcher. What once looked smart now seems frumpy.

— Pearls: gorgeous though they are, they tend to be age-specific, ie, lovely on older women, not quite right on twentysomethings.

— Root-lifted hair: you didn’t really think that this was a good idea, did you? Get a good cut.

— Sheer tights: too old for anyone under 60.

— Fur: so ageing, it’s dead. It doesn’t belong on anyone.

— “Baby” colours: these, especially powder blues, look sickly. Nowadays a pastel blue needs some grey or brown in it. Pinks should be slightly “dirty”. However, pastels can look chic on those with grey or white hair.

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