These are the things Meghan and Harry aren't allowed to wear on their wedding day

And wait 'til you see the wedding guest rules

Royal fashion etiquette is a law unto itself, from dictating which kind of bag Kate Middleton should wear to whether or not Princess Diana was allowed to wear gloves. So it comes as no surprise that the Royal wedding has a very strict dress code.

The wedding invites went out months ago, and the formal dress code was set: day dresses and hats for the women; uniforms, morning coats, or lounge suits for the men. But there are a few other rules wedding guests are expected to follow, as well as Prince Harry and Meghan Markle, so here's a breakdown which will especially be handy for non-Royal and non-British guests - well, we wouldn't want a sartorial faux pas from Meghan's Suits castmates now, would we?

Female guests should wear hats and day dresses for the day

Beatrice and Eugenie didn't just wear hats to become the meme of the year (well, pretty sure that wasn't their intention either), they had to. Ladies must wear hats in church as a sign of respect, and the bigger and more jovial the better. However, hats aren't recommended for the evening, as that's when the tiaras come out. For the day, dresses are expected to be on the conservative side (it's a church wedding after all), and colour is encouraged, though of course black and white are discouraged.

For the evening, expect guests to wear fancier and longer dresses.

Male guests should wear uniforms, morning coats or lounge suits

According to Town & Country, military men are encouraged to wear their uniforms, but failing that, a morning coat and all the trimmings is a must. Think tail coat, waistcoat, tie etc, though if that's not their bag, a lounge suit, which despite the name is really just a nice suit, is allowed. However it's deemed 'inappropriate' for men to wear hats, and polished black shoes are a must.

Prince Harry will probably wear a uniform

When Prince William married Kate, he wore his uniform, and as Harry was in the military too, it's likely he will follow suit as it's traditional for Royal men to do so.

Meghan Markle's bouquet will have myrtle

According to Bustle, it's a Royal tradition to include myrtle in the wedding bouquet, as it symbolises love. It all started when Victoria included a sprig in her bouquet, and it has since been grown in the Royal garden. Princess Diana, Kate Middleton and the Queen all had it in theirs.

Meghan Markle will have a classic manicure

No bold colours for Meghan, as only neutral manis are allowed for Royal events.

The bride's wedding ring must contain Welsh gold

Another tradition, started by the Queen's parents. When they got married, they got given a gold nugget from a mine in North Wales, and a bit has been used for each Royal bride since.

Meghan Markle's wedding dress will be by a British designer

This isn't official, but since Queen Victoria, The Queen, Princess Diana and Kate Middleton all wore British designers, it's safe to assume Meghan will follow suit. Which ties into the whole Erdem designing the wedding dress very nicely indeed.