But whatever the protocol, Meghan clearly still controls her own wardrobe and opted for a dress reminiscent of the Givenchy design she wore on her big day.
The Duchess looked absolutely gorgeous in her bespoke Carolina Herrera dress and matching Philip Treacy hat.
"I think right now in the climate that we're seeing with so many campaigns, #MeToo and Time's Up, there is no better time than to really shine a light on women feeling empowered and people really helping to support them, men included in that", she added.
Markle handled her debut on the balcony with grace and ease, but of course, she's still getting used to being a royal, so it's no wonder she needed a little assistance from husband Prince Harry at the event as well.
"[Meghan] was still in a good position".
In addition to the Queen, Prince William and Kate Middleton, and their children, Prince George and Princess Charlotte (Prince Louis stayed home during the festivities!). As usual, they also looked adorable for this major royal family photo op, with their 7-year-old cousin Savannah Phillips nearly stealing the show by pretending to conduct the orchestra or by putting her hand over George's mouth.
When asked whether the Duchess had approached her with ideas, the 46-year-old replied: 'Yeah, we worked together.
Meghan has no doubt learned the royal etiquette rules from watching the royal family over the past few months.