A funny thing happened in Zara last week. I found myself in the changing room trying on a pair of shorts — and I mean short shorts, not the ones that end just above the knee or the kind that could be a skirt, with their flared legs and front pleats.

I am in my mid-forties. My legs are certainly no fitter than they were this time last year, when there were shorts in the shops, but it didn’t cross my mind to actually try any on, let alone buy some. I don’t own a pair of leggings, I don’t do mid-thigh minidresses. Yet, suddenly, I have no inhibitions about trying on sawn-off denim shorts and walking out into the street wearing them (as it happens, I didn’t, but had I, it would have felt totally normal. Like pulling on a pair of Ugg boots).

Who knows why it has happened, but short has become something your mother would never have dreamt possible: mainstream and everyday for everyone who can take it. And the big difference is, more of us than ever can. You don’t need amazing legs to go short any more. You don’t have to be young. Trust me, by Christmas there will not be a fashion-lusting woman in Britain under 50 who doesn’t own some kind of shorts — and to hell with it. Shorter hemlines are now a fashion fact — not only the hot choice for hot girls — and shorts are the easy-going alternative.

If you feel unsure about a high hemline — you think it’s too provocative, too mutton-dressed-as-lamb or too attention-seeking — then shorts are a sportier, safer alternative. More businesslike for work. Less risky on the escalator. With shorts, it’s much easier to vary the message: wear them with a tight vest and heels and you are Rollergirl (not for everyone); pull them on with opaques and flat pumps, and sling a big blazer on top, and you are Amélie, or just a girl on her way to the office.

We’re not saying shorts can’t be breathtakingly sexy (and there are plenty of sizzling hot pants out there), but they are also very versatile. And you can go shorter in shorts than you can in a dress, without causing the wrong kind of sensation, as long as you stick to the rules.

DOs AND DON'Ts

DO hit the shops There is a pair out there for everyone. From the smooth, shiny-ponytailed executive (tailored, black) to the punky teenage model (tie-dye denim from Pepe). One trawl of Topshop and you will find sailor girl, candy stripes with turn-ups (perfect for Kelly Brook), sawn-off denim (Kate Moss), tidier denim (Kylie) or floaty, flippy numbers (Chloë Sevigny).

DO get going on leg preparation You need a good exfoliator, plus a tanning product. Johnson’s Holiday Skin body lotion (£4.88 for 250ml) is brilliant — it not only gives instant glowing colour, but works on developing a tan underneath. A cover-up stick is good to hide broken veins or bruises from riding your bicycle. Alternatively, you may just want to keep your tights on for as long as you possibly can.

DO go up a size Too tight and too high-cut equals too seedy.

DO embrace opaques Luckily for us, black opaques and shorts — particularly denim — go together like fags and Kate Moss. They are not merely a great chicken-skin concealer, they also make all shorts look automatically chicer (which is why Kylie, who likes to dress up, wore denim shorts and tights to Nobu the other night). Make sure they are opaque — any old black tights under shorts will make you look like a district nurse, and not in a good way.

DO add a blazer or long cardigan Let it graze the hem of the shorts to soften their impact and give them a cute, sophisticated edge (think Alexa Chung).

DO remember you cannot go wrong with denim And they don’t have to be indigo. White, light blue and beige are hot for summer.

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