fashionista who shook up the royal dress code

London : Princess Diana revolutionised the royal dress code with the help of some of the world's greatest designers during a glamorous life that came to a tragic end 20 years ago this month.

"Diana has become a fashion icon in the same way as Jackie Kennedy or Audrey Hepburn -- timeless, elegant, and still so relevant," said Eleri Lynn, curator of "Diana: Her Fashion Story", an exhibition at her Kensington Palace home in London.

Nicknamed "Shy Di" ahead of her marriage to Prince Charles, the heir to the throne, in 1981, Dianacame out of her shell and realised how her clothes could be used as a powerful communication tool.

"The princess learned to make her wardrobe say what she could not, and worked closely with designers like Catherine Walker to curate her personality through clothes," Sophie Goodwin, fashion director of Tatler magazine, told The New York Times in February.

Diana mastered the art of wearing the right dress for the right occasion.

She wore bright clothes when visiting hospices, in order to appear warm and accessible.

On foreign visits, she would chose clothes inspired by the national colours, such as the white dresswith red spots she wore on the trip to Japan in 1986.

She chose not to wear gloves "because she liked to make contact with the people she was meeting", said Lynn.

Pictures of the princess shaking hands with AIDS patients in 1987 helped to break down myths surrounding the disease, including the unfounded fear of being able to catch it through touching sufferers.

The most photographed woman of the age, Diana understood the rules of royal dressing but was not afraid of twisting them.

She breached royal protocol by wearing a black ballgown, a colour worn formally by royal women only during mourning.

Her outfits included androgynous gear, such as a tuxedo and a bow tie.

"That's quite the bold, fun look that you don't necessarily expect of a princess," said Lynn.

She said Diana was the first woman in the royal family to wear trousers to an evening event.