If you're going with the royal theme for your party, you might as well go all the way and enforce a dress code. In your invitations, make it clear that everyone should be arriving in something they would wear to the royal wedding. This is a fun way for people to get creative with hats, and they can also deck themselves out in their best wedding looks — including, obviously, hats for the ladies. You can also pick up a bunch of fake tiaras and crowns (Etsy, $5.39) from a party store to give out to everyone showing up. That way, you can all be royals for the day (or night).

It wouldn't be a theme party without the right decorations, and luckily for you, there is a ton of royal wedding merch out there that will make for some truly awesome decor. You can decorate cupcakes or cookies with royal wedding toppers (Etsy, $2.34), hang some royal bunting (Etsy, $7.47), put out some royal plates (Etsy, $5.47), and drink out of royal wedding plastic cups (Etsy, $35).

Instead of just doing a royal wedding theme for your party, make it all about the actual event itself. Merge your birthday and the wedding together with a viewing party — the wedding will begin at 7 A.M. EST (12 P.M. GMT) on May 19. Set out some tea and crumpets, since it will be early in the morning, and invite everyone to take part in the festivities with you. Or, if that's way too early, DVR it, and you can all watch together later in the day.

Want to do more than just hang out and watch the royal wedding? Set up some fun themed games. You can set out a little true/false trivia game (Etsy, $2.83) if you want to keep things tame, or a royal wedding drinking game if you want things to get a little out of control (Etsy, $2.83). If you plan on doing a viewing party, there's royal wedding Bingo cards you can download (Etsy, $5). This royal wedding party pack comes with a few different games, as well as royal invitations (Etsy, $19).

If you want to get in the British spirit of things, start by only serving some food that's popular on the other side of the pond. The most obvious choices are biscuits and tea, but if you want more than that, there are plenty of other food items you can put out. This includes fish and chips, mushy peas, Yorkshire pudding, bangers and mash, and maybe some mince pie.

If making all of that sounds like a terrible idea, make reservations at a British pub or restaurant near you in your honor. You deserve a good meal for your birthday!

Maybe you want your party to be more on the elegant and understated side, rather than something more rowdy. If so, do a little tea party. You can serve royal wedding tea (Amazon, $19.99), and adorable English biscuits (Biscuiteers, £45). It's definitely a very unique idea that could be a lot of fun.

There are so many details about the royal wedding that you could basically imitate it for your birthday party if you really wanted to. Instead of doing silly decorations, do something more authentic by "borrowing" ideas from the royal wedding.

Kensington Palace announced in March that Meghan and Harry would be serving a lemon elderflower cake, so you can make elderflower cupcakes or cakes at your party. We also know that Meghan loves peonies, so you can get a bunch of those to decorate with. You can even put out fake diamond rings for guests to wear.

Get everyone into the theme with some props that would make for hilarious photos. You can include life-size cut-outs of Meghan and Harry (Amazon, $99), as well as royal masks people can wear in photos. And of course, don't forget a mask of your own face as well, since you're the birthday girl! There are also royal photobooth props (Etsy, $6.22) that would be fun to include as well.

Another more low-key idea is to have a royal-themed movie night with your closest friends. You can wear your birthday tiara and just watch a bunch of movies about the royal family. Some examples include The King's Speech, The Queen, The Young Victoria, and The Crown.