Your 40s is the decade to upgrade your choice of fabric and cut. 
Dressing well shouldn’t be simply a matter of weight, and it shouldn’t simply be a matter of age either. We’re all aware that a 40 or 50-year old can’t dress like a teenager – that’s just plain sad. But once you hit 30, I reckon, you can start developing a personal style that can take you, with annual updates, through the rest of your life.
So what should it be based on? Here are some handy ‘rules’ – rules in the sense of ‘for the obedience of fools and the guidance of wise women’…
1 Dress like a grown-up
You are not a little girl any more, so knock off the ruffles and bows and all the cutesy, ditsy stuff. Shorty ra-ra skirts, itsy-bitsy little tops, girly prints, t-shirts with bunnies on or ‘sexy’ sayings. These are no longer for you. Instead, look for reserved, adult clothing with some structure and shape to it. Long sleeves on tops, long legs on trousers, whatever necklines are most flattering for you personally, clothing without bells and whistles, classic block colours – black, white, navy, cream and good neutrals. Build your wardrobe around these items and then add your own twist and flair.
2 Keep it covered
I don’t mean nun-like, but in general, follow the 30 per cent rule – only show 30 per cent of your body at any one time, even for evening. Now is the time to look like a woman who’s actually getting sex, rather than desperately looking for it. If you’ve got great arms, by all means wear a sleeveless top, but keep the neck high for maximum impact and cover your legs. If you’re wearing backless, keep the front high: if you’re wearing a plunge front, keep the back high… The fact is: if you reveal your flesh, you are going to be compared with every 20-year-old who does the same – it is far better to leave people guessing about how gorgeous you are than to show them you’re not.
3 Keep it simple
There’s a good reason I’ve banged on endlessly in this blog about ‘classic clothes’, and that’s because they work. And one key thing that differentiates classic clothes is that they have simple lines – their design is pared down to the essentials. Whatever you’re wearing, seek simplicity and avoid exaggeration. Don’t wear things with 25 colours and added bits of gewgaws all over them – contrasting appliques and heavy beading in clashing colours. Avoid big shoulders, poofy skirts, huge floppy collars and lapels, and weird sleeve designs. These don’t do anyone any favours – even teenagers, but teenagers have a right to look stupid if they want to. Grown up girls need to raise the bar a little – aiming for elegance and class. Keeping it simple works with any type of clothing – blouses with small collars, t-shirts with scoop or v necks, blouses with clean French cuffs, pencil skirts, clean-lined jackets with vertical seaming….
4 Keep it clean
When I say clean, I do mean physically clean. Being scruffy is the prerogative of the young, the rich and the mad, but the rest of us have to conform a little even if we may not like it. Going out with chipped nail polish, undyed roots, a moustache or clothes covered in dog hair just screams middle-aged rut, and don’t think that people won’t notice because they will. Grown-up girls have to look groomed. Not polished necessarily, but soignée, as the French say – cared-for, put-together. A clean, crisp, groomed appearance always works, no matter what your lifestyle.
Yes, it takes a little application, but the effort repays itself a hundred-fold. Choose a haircut that you can maintain easily (or pay to have maintained). Keep your clothes clean (if you can’t afford or don’t wish to undertake dry cleaning, buy clothes you can wash at home). Do running repairs once a month – sewing buttons back on and taking your shoes for re-heeling. Iron things properly and treat stains before they set. Overall, treat your clothing as if it cost ten times the price.
5 Keep it quality
Quality wears better than rubbish, and whatever the item, quality cloth, cut and finish will show. Buy quality items wherever you can, even for basics – pima cotton t-shirts, Egyptian cotton blouses, cashmere and merino knitwear in plain colours, decent wool-rich suiting (a little stretch here can work wonders), a fantastic pair of jeans with the outside seam brought slightly forward to slim your thighs, and correct pocket placement. Watch out for the sales and stock up on basics from good manufacturers. It is better to have a smaller wardrobe of quality items than a large wardrobe of tat – the age of 40 is a good signal to upgrade your choice of fabric and cut.
When I say quality, this is quality at every level, so if you’re strapped for cash, go for the best of a type. Rather than buying low-end fakes of high-end items, look for high-end democratic items at a lower price level. Instead of tinny gold-plate jewellery, buy handmade wooden beads; instead of a plastic leather-look handbag, buy a good-quality canvas bag; if you can’t afford cashmere, buy merino on sale rather than a cheap acrylic sweater. In the long run, it will pay dividends.