A great style icon, Princess Diana in her life always looked radiant and groomed whenever she showed up in public. [Photo/Agencies]

She was the most photographed woman in the world from the early '80s up until the time of her death in 1997, and Princess Diana rarely put a foot wrong. While she is still name-checked as one of the greatest style icons, she was equally as influential when it came to her hair and makeup.

Diana never looked anything but radiant and groomed. Despite being a princess and having access to some of the best experts in the industry, Diana impressively always looked flawless, but approachable. Here are the timeless lessons we should all take from her...

Look after your skin

Diana's former makeup artist Mary Greenwell has revealed details of the princess' beauty regime over the years. She was a follower of the cleanse, tone and moisturize routine (she was introduced to Clinique by Felicity Clark, Vogue's beauty director in the '80s and a close friend of Diana's), and she always took off her makeup at the end of the day.

While maintaining her healthy glow was part of the reason for her stringent regime, Diana also battled with rosacea on her cheeks, so removing makeup and rehydrating her skin was essential to soothing the condition.

Embrace color

Admittedly it was a look that Greenwell weaned Diana off, but we're still impressed with her channeling of blue eyeliner in the '80s.

Greenwell's bug bear with it was that matching your liner with your eye color isn't the most flattering look. Instead, she encouraged Diana to embrace black liner sparingly and plenty of mascara for a fresher, brighter eye look.

In the '90s, Diana found a new way to inject some color into her look with statement red nail polish. She was regularly photographed with perfectly manicured hands.

Bold to experiment

She was known for her blonde bouffant, but perhaps one of Diana's most iconic beauty moments was when she arrived at the CFDAs in New York with wet-look hair. While she had trialled the style in private with her hairstylist at the time Sam McKnight, Diana had never been seen in public with such a strong look.

Mix up your exercise

Dancing, skiing, jogging, you name it, Diana was known to enjoy working out. With Kensington Palace Gardens on her doorstep, she would regularly start the day with a jog around the park, accompanied by a bodyguard and she was regularly photographed arriving at Chelsea's Harbour Club gym. Dancing was part hobby, part exercise, as Diana danced from a young age. The princess was never seen looking anything but trim and toned, proving that mixing up your routine and finding the fitness style that you enjoy can pay dividends.

Maintain your tan

Being conscious of the press accusing her of looking pale or wane, it's rumored that the princess had a sunbed at the palace that she would use several times a week to maintain her sun-kissed glow. While we wouldn't recommend sunbeds, Diana was proof that a light tan does give you that healthy glow.

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