How to dress like a princess

Princess Mary of Denmark, the Duchess of Cambridge, and Queen Letizia of Spain. Photos / Getty Images

It used to be so easy. A flashy tiara, a dress the size of a van, a tub of white lead powder and a casually-slung ermine were enough to denote power and inspire loyalty. But in this godforsaken age of topless sunbathing and Las Vegas pool parties, crinolines and crowns are no longer the default setting for princesses.

Perhaps that's down to the fact that the monarchy today has virtually no power, its only merit - in Britain, at least - being that it attracts American tourists and ensures the steady sale of thimbles in spite of the fact that nobody sews anymore. The public appeal of a desperately anachronistic spectacle, however, cannot be understated. And if good causes are to be supported, it needs to be harnessed. Now more than ever, royal-watching is a popular, full-time occupation. Why? Because if there's one thing that fascinates us about princesses more than the slow attrition of their soft power, it's their wardrobes - and the messages they undoubtedly transmit with their clothes.

Pity the modern princess, caught between wearing something pricey and designer, which guarantees ensuing allegations that she is out of touch, and something bargainous from Zara, which will lead to cries that she is neglecting homegrown designers and cheapening her office.

An air of studied normality is jarring - you're a duchess, for goodness' sake, so ditch the Topshop - while anything too sexy is also verboten if a tabloid frenzy is to be avoided.

So what's the formula for princess-dressing in 2014, when modern royals are supposed to live as modestly as school teachers while inhabiting palaces? We read the runes of the royals and took some tips.

Duchess of Cambridge

A Duchess by name, but a princess in every other sense, Kate Middleton has morphed from a Home Counties belle into the beautiful yardstick by which all other royals are judged.

The Duchess deploys the raised-waist tactic. Photos / Getty Images

Go-to brands: Alexander McQueen, Emilia Wickstead, LK Bennett - all topped off with a Kings Road blow-dry.

Princess proclivity: The raised-waist tactic. Kate is a master of alterations, regularly getting her high street purchases taken in by the Buckingham Palace mice so that they sit a centimetre or so above her natural waist to give the illusion of longer legs.

Gallery: Kate Middleton's pregnancy style

Queen Letizia of Spain

Not technically a princess - she upgraded to Queen when her husband, King Felipe VI, ascended in June 2014 on the abdication of his father - but she's always immaculate so we're including her anyway.

Queen Letizia of Spain in lace. Photos / Getty Images

Go-to brands: Felipe Varela, Hugo Boss, Zara.

Princess proclivity: Lace. Guipere lace, to be precise, and usually in the form of a figure-hugging sheath dress. It looks traditional but not stuffy, and allows for a hint of Spanish sassiness when worn off the shoulders.

Princess Mary of Denmark

Tasmania-born Mary met her Prince Frederik at the pub during the Sydney Olympics in 2000. She once worked for an advertising agency; now she conducts tours aboard the Royal Yacht Dannebrog.

Princess Mary of Denmark favours heels by Christian Louboutin, Gianvito Rossi and Rupert Sanderson. Photos / Getty Images

Go-to brands: Prada, Dolce & Gabbana, Hugo Boss.

Princess proclivity: Great shoes. Whether its racy snakeskin Christian Louboutin court shoes, Rupert Sanderson patent stilettos, Isabel Marant ankle boots or Gianvito Rossi leopard print heels, Mary knows the shoe maketh the outfit.

Princess Charlene of Monaco

A former Olympic swimmer, South Africa-born, and 20 years her husband's junior, Charlene is saddled with the myth of her mother-in-law, Princess Grace. Still, she's embraced fashion wholeheartedly, donating three Akris outfits to the Design Museum's latest exhibition.

Neckline time: Princess Charlene's various neckline styles on her outfits. Photos / Getty Images

Go-to brands: Akris, Armani, Christian Dior.

Princess proclivity: An interesting neckline. She's hardly broad, but with those swimmer's shoulders and a champagne crop, Charlene knows a little distraction at the neckline is crucial. She favours keyhole cuts, peter pan collars, high-necks and asymmetric shapes and keeps accessories to a minimum.

Princess Marie-Chantal of Greece

The daughter of an American duty-free billionaire with the hair to match, Marie-Chantal owns a posh childrenswear line, and once worked as an assistant at Andy Warhol's Factory before falling in love at first sight with (now exiled) Prince Pavlos.

Princess Marie-Chantal finishes her outfits with jazzy earrings. Photos / Getty Images

Go-to brands: Chloé, Valentino, Céline, Diane von Furstenberg.

Princess proclivity: Jazzy earrings. Even when she's whacked a tiara on that golden halo of follicular loveliness, Marie-Chantal can't resist a pair of Loree Rodkin diamond-encrusted sparklers to top off the outfit.