Kate Middleton and Meghan Markle
Meghan Markle already knows how to sit in a "duchess slant" similar to Kate Middleton. Pictured: Middleton and Markle attend the first annual Royal Foundation Forum held at Aviva on Feb. 28, 2018 in London. Getty Images/Chris Jackson

Meghan Markle has copied the way Kate Middleton and Princess Diana sit.

On Wednesday, the "Suits" star and the Duchess of Cambridge made their first official royal engagement together. The two women sat beside each other, so their manner of sitting was easily compared.

Markle, who will be joining the royal family soon, was photographed sitting in "the duchess slant." The position involves keeping the knees and ankles tucked closely together while the legs are slanted to the side.

"Typically the 'duchess slant' is used when a lady has to sit for an extended amount of time while keeping poise and posture," Myka Meier, royal etiquette expert and founder and director of Beaumont Etiquette, told People. "It is the perfect pose for when a camera is shooting directly in front of you because by slightly slanting the knees to create a zig-zag effect when wearing a dress or skirt, your legs are angled so that the camera only shoots the sides of your legs and protects your modesty."

Meier added that the "duchess slant" is one of the most elegant and flattering ways to sit because it also makes one's leg appear longer. The royal etiquette expert shared some tips to perfect this position.

"The key with the technique is to square your shoulders straight ahead while maintaining perfect posture," Meier said. "Keeping knees and ankles together at all times, position your legs so that you create a slant, angling your knees to the side. Hands should be folded one over the other and placed in your lap."

Although Markle has started sitting in the "duchess slant" manner, she has photos crossing her legs, which is a big no-no for the royals. This did not go unnoticed to Prince Charles' former butler Grant Harrold.

"Her Royal Highness The Duchess of Cambridge is sitting in a correct and ladylike manner, which she would have been taught at an early age," Harrold told Daily Mail.

Grant explained that this sitting position is not only correct, it is also ladylike. It is a practical way to protect one's modesty when wearing a skirt or dress. The butler stressed that ladies would not normally cross their legs at the knees.

Grant also commented on Markle's first curtsy back in December. According to him, Middleton did it right while the "Remember Me" star dipped too low. In addition, Markle made a mistake when she bowed her head.