On and on the boiling weather goes and, love it or hate it, we have all had to adjust our dressing accordingly.During the first wave you could huff and puff and protest that you weren't prepared; now we are several waves in and there are no excuses left.No need to tell you dressing doesn't get tougher than this. Looking good and feeling good in 30C (86F) – in the city rather than at the beach – is the trickiest fashion challenge there is, and, as we all know, it doesn't get easier with experience. The British midlifer – and those of us who are 50-plus in particular – need all the help we can get.So here are a few heatwave dressing dos and don'ts . . .WOMENDon't choose bright huesYou only have to look at the number of celebrities who chose white at Wimbledon to conclude that white (or cream) has leapfrogged back to first position for dressing in the heat at any age.Singer Katherine Jenkins wore a sharp white trouser suit, Queen Camilla's sister, Annabel Elliot, wore a notch-neck, short-sleeved white dress and Carole Middleton's cotton maxi from Me+Em was plain white under a blue linen blazer.The only thing chicer in the searing heat? Black and white of course. Poppy Delevingne's fitted white top and black palazzo wide trousers was a look any of us could adapt (her top was strapless). And Daisy Edgar-Jones looked effortlessly stylish in her monochrome Chanel that was straight off the fashion house's red-hot 2027 Resort collection.Naomi Watts, in the front row at Balenciaga in Paris last week, looked perfectly cool in a white dress shirt and black trousers. And the reverse – a white ankle-grazing skirt with a black short sleeved or sleeveless top – is emerging as another classic heatwave look. Apologies to Sam Taylor-Johnson (pictured, left, with Aaron Taylor-Johnson at Wimbledon) for being picky – the waistcoat wasn't a neat enough fit, the shorts were a bit too short Sienna Miller pictured wearing a pale grey Heatwave Suit at Wimbledon last week, with XL wide trousers. The Heatwave Suit flows like a maxi below the waist and gives you optionsDon't opt for waftyIt has numerous advantages, namely excellent air circulation, but unless you're a willowy young thing, or at the beach, it's hard to avoid looking blobby in something loose and airy. If you want to go the waft route you need a deep V-neckline, an empire waist, bracelet-length sleeves (baring six inches of skin above the wrist helps) and a light-coloured fabric. Avoid a print.Don't go flimsySheer, like cling fit, is a bad idea for the average 50-pluser and, in the heat, it won't keep you cool. Light cottons are the answer and uncreasable options like double cloth and seersucker – and whatever you do, avoid man-made fabrics.Don't bare arms and legsSam Taylor-Johnson's Wimbledon outfit was close to being top heatwave wear (waistcoat with nothing underneath, tick; white, tick; shorts tick), but we're looking for heatwave ten out of tens here. So, apologies to Sam for being picky – the waistcoat wasn't a neat enough fit, the shorts were a bit too short and the high-heeled sandals were too couture and unbalanced the rest.Were the shorts longer – knee-grazing or covering – the heels would have worked. Note: the proportions have nothing to do with how good your legs are. On 50-plusers it's better to steer towards a knee-length hemline unless you're at the beach.Don't wear heavy shoesThe wrong footwear – heavy, wintry looking – can sabotage your on-point heatwave outfit faster than running make-up. Heels must be pale coloured or white (black ballerina pumps are the exception). But the footwear that looks best now is a strappy sandal or slingback.If you're wearing trousers or an almost maxi hemline, showing a glimpse of foot skin lightens the look instantly.Don't keep the black bagIn a heatwave, even a black Hermes Kelly bag looks like a doctor's bag (a misstep from Elle Fanning in the glaring sun at Wimbledon last week). A light leather, pale tan, basket weave or raffia bag looks heatwave chic.Don't wear tightsEver. They're hot and 100 per cent ageing, especially with sandals. If you don't feel your feet are up to exposure, wear a closed toe.Don't go for silkSienna Miller can get away with a silk slip under a fur coat in a heatwave and Victoria Beckham may have donned one of her own silk tops for the England v Norway World Cup quarter final, but silk does not 'breathe' and we regular civilians sweat in it. In a heatwave, even a black Hermes Kelly bag looks like a doctor's bag (a misstep from Elle Fanning in the glaring sun at Wimbledon last week) Daisy Edgar-Jones, pictured at Wimbledon on Sunday, looked effortlessly stylish in her monochrome Chanel that was straight off the fashion house's red-hot 2027 Resort collection Victoria Beckham may have donned one of her own silk tops for the England v Norway World Cup quarter final, but silk does not 'breathe' and we regular civilians sweat in itDo choose tailoringJust because something has structure doesn't mean it has to be hot or restricting (see Nicole Kidman). A plain linen jacket worn over a short-sleeved dress will protect you from the sun, make you look pulled together, and you have the option of taking it off later.The new heatwave saviour is the waistcoat with nothing underneath, plus tailored trousers – it's what you wear if you want to look sharp but not covered up. Everyone from Arthur Fery's 53-year-old mum, Olivia, to Victoria Beckham has been trying it.Also known as the adaptable three-piece. Sienna Miller was wearing a pale grey Heatwave Suit at Wimbledon last week, with XL wide trousers. The Heatwave Suit flows like a maxi below the waist, fits like a glove above it, and gives you options. Roll up the sleeves Sienna style or shoulder robe your jacket.Do go longer in the heatYou will feel cooler in extreme heat in a long-sleeved shirt dress (actress Jodie Foster at Wimbledon), or an ankle-grazing maxi skirt and short-sleeved shirt (Anna Wintour's front-row heatwave uniform).Longer hemlines look breezier in hot weather and mean you never need to bother with fake tan. Longer sleeves keep you cool. You have to be beanpole slim to get away with both, mind you – as Wintour sometimes does – so for civilians it's one or the other.Do ditch holiday togsResist the temptation to reach for that shocking-pink maxi kaftan or the minidress you wear over your swimming costume at lunchtime. Heatwave rules at home are different and it's important to remember what works on holiday is very different.MENDon't wear all whiteYou'll look like yachting crew. Instead go for cream. See Dominic West whose double-breasted cream linen suit knocked spots off comic Jack Whitehall's mix of white trousers, white shirt and grey jacket at Wimbledon and Oli Green whose buttery linen suit was one of the standout men's looks of the fortnight.Don't go for trunks...If you're under the impression that everyone thinks trunks look like shorts, they don't, and furthermore, they may be slightly see-through. Avoid.... or short shortsAs Andy Burnham discovered, the running shorts you've owned since you were in your 20s are now for Harry Styles types only. And yours need to be longer – and longer still for everyday life.Don't wear sandalsBy all means go the Andy Burnham Birkenstock route at the weekend, but more coverage is required in smarter settings like the office. And never resort to flip-flops unless on holiday.Don't unbutton shirtsTwo undone buttons is plenty. Likewise, don't roll up your sleeves too neatly so they look like a couple of water wings.Do wear a jacketIn a heatwave the loose fit, creased linen shirt worn out over trousers is the number one male fashion mistake. It seems counterintuitive, but a linen jacket over a pale shirt will make you look, and feel, cooler. Jackets cover creases and sweat stains and sharpen your silhouette as Bear Grylls, the person you voted best-dressed at Wimbledon in our online poll, showed. You might consider a belt for the same reason.Do go for pale coloursSecond most common heatwave fashion mistake – sticking to darks with dark leather shoes and socks. Lighten up like actors Joseph Fiennes and Tom Hiddleston at Centre Court last week. Try light khaki trousers, a white shirt and tan shoes, or a beige jacket over a sky-blue shirt. Just because something has structure doesn't mean it has to be hot or restricting (see Nicole Kidman, pictured at Wimbledon on Sunday)Do wear a hatOr your face will turn the colour of beetroot (all women know about hats).Do think about footwearMen also need to go lighter in the colour and weight of footwear. A heavy black Chelsea boot under a pale linen suit will kill it. Black suede is banned as are brogues, unless you're wearing a suit. Tan leather or brown suede is your best option. And plain tan or cream trainers are the best heatwave-friendly smart-casual shoes.Do pick cotton or linenPut away the polo shirt, the T-shirt and any short-sleeved tops and switch to a light, but not baggy, long-sleeved shirt.