13. Curtsies Are Strongly Suggested

Reason: It is a show of deference.
Excemption: While it’s customary, it’s not required.
Even though there are no “obligatory” guidelines to follow when visiting the Royal Family, the official website of the British Monarchy does concede that some visitors may like to follow custom.
Curtsies are strongly promoted. Copyright: Samir Hussein/Getty Images
This means that when encountering a member of the Royal Family, men should bow (with their neck, again, nothing spectacular) and ladies should curtsy (just a little, crossed ankle kind of thing).