Being a princess might seem like a dream, but in reality, the title comes with a lot of rules. After all, the Royal Family are very traditional and constantly being in the public eye means there is careful scrutiny over how well those traditions are being upheld.

In fact, fashion is a rather complicated issue for the Royals. It might seem like they have a lot of freedom with their outlandish fascinators and designer wedding gowns, but there are plenty of rules for what a Royal can wear.

Here are 12 of the most puzzling…

1. Tiaras are not for everyone

Tiaras are only for married women and it is expected that the first time a Royal will wear one will be on her wedding day. Kate Middleton borrowed Queen Elizabeth’s Cartier Halo tiara for her wedding to Prince William in 2011.

“It signals the crowning of love and the loss of innocence to marriage,” explained Geoffrey Munn, author of Tiaras – A History of Splendour. Therefore it’s likely that Meghan Markle will wear one to wed Prince Harry this May. It will be interesting to see which one she chooses.

2. Natural nails only

The Royals are not allowed to wear colored nail polish. Neutrals like light pink or taupe are fine, but bright reds, blues, or turquoises are a definite no-no. Case in point, take a look at Kate’s unpolished nails in the photo above.

3. The Queen always wears bright clothing in public

While colored nails won’t be happening anytime soon, the Queen is no stranger to brighter hues when it comes to her clothing. However, it’s not because she likes those monotoned purple or green head to toe looks, it’s so that she can be spotted in a crowd.

Sophie, Countess of Wessex (the Queen’s daughter-in-law), explained, “She needs to stand out for people to be able to say ‘I saw the Queen.'”

4. The Queen always wears a hat

The Queen is very traditional, and so keeping with the old tradition that ladies should never show their hair in public, she almost always wears a matching hat with her colorful outfits.

“Up until the 1950s, ladies were very seldom seen without a hat as it was not considered ‘the thing’ for ladies to show their hair in public,” revealed Diana Mather from The English Manner etiquette consultancy.

Check out number five to see how the Queen uses her accessories to send secret messages!