The mother-of-three will regularly attract attention when she steps out with many royal fans looking to see what she wears.
She has developed her own look and will often recycle looks and wear pieces from affordable high street brands.
There are also some style rules that the royal must follow, stylist Melita Latham told Express.co.uk.
Melita said: “There can be no other sign that you’ve morphed into a royal than a change of dress, particularly post children.
“Whilst I’m sure Kate wanders around Kensington Palace in joggers and a T-shirt, just like the rest of us, while in the public eye her ensemble is more than sensible.”
Royal style rules mean ditching anything that is too low cut or with hemlines above the knee.
It is also thought the Queen prefers royal women to wear skirts and dresses over trousers.
Kate has been known to follow most rules but the expert claimed she could use her shoes to make a statement.
The expert continued: “Her extraordinary figure, height and posture looks amazing in the style of dress that many of us would struggle with.
“During a visit to the London Natural History Museum, Kate looked simply amazing in Forest Green culottes and a burgundy knit with heels.
“This is Kate’s ‘vogue’. Sensible, slim, long legged and understated but oozing confidence and perfect for ease of movement. The perfect working outfit.”
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The royal line of succession – who outranks who?
The line of succession to the British throne dictates the order in which each member of the Royal Family would ascend to the throne.
It is also seen as a ranking of importance with the head of the line, the Queen, taking the place of ruler.
Older children come before younger children. Traditionally boys came before girls, but this law was changed on 26 March 2015 before the birth of Prince William’s first child.
Incredibly, Catholics are still excluded from the line of succession, as are children born outside of wedlock.
The royals, who usually stick to a strict protocol when appearing in public, often arrive at events in ascending order of importance, with the most important royal arriving last.
Prince Charles, 71, is currently second-in-line to the British throne, followed by Prince William, 38, his oldest son.
Then comes Prince William’s children, George, seven, Charlotte, five, and Louis, two, and they are followed by Prince Harry, 35. Prince Harry is succeeded by his son Archie Harrison, born in May 2019.