I, Bridesmaid #14, vow not to post photos of the bride before the ceremony.

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There’s no excuse for bad manners. Good manners are free of charge, easy to employ, and bona fide evidence that your mama and daddy raised you right. But sometimes, matters of etiquette prove trickier than you might expect, so we’re here to set the record straight. Consider it your Southern Living guide to modern manners. Be polite, or die trying, y’all.

Let’s talk weddings.

When it comes to practicing proper etiquette, weddings are a veritable minefield: Is it okay to wear black for a winter wedding? What about red? Is black-tie optional really optional? What’s the best time to thank the brides’ parents? And if you’re friends with both the bride and the groom, which side do you sit on?

There are a lot of opportunities to get it wrong when it comes to wedding etiquette. And social media offers further territory that’s dangerous to navigate. Today we’re tackling the stickiest of them all:

When is it appropriate to share photos on social media?

If it’s your own wedding, you can send out a selfie from the altar, for all I care. Your grandmother might fall out because of it, but hey: It’s your day; you make the rules.

For the rest of us, whether mother-of-the-bride or lowly guest, the answer is far more nuanced. Before we even talk sharing the photos, let’s discuss taking photos.

You should never take photos during the ceremony—whether it’s happening in a cathedral or the backyard—unless you’ve been explicitly asked to do so by the happy couple (or they’ve paid you to because you are, in fact, the wedding photographer). The risk of interrupting a sacred moment with a blinding flash or obnoxious click-beep-ring is too great to warrant any mid-ceremony shots, no matter how tempting. So the appropriate time to share ceremony photos is never, as you shouldn’t even haveany to share. (One exception: Family members and wedding party members may share professional photos of the wedding ceremony, with the express permission of the couple and the photographer, after the bride and groom have already shared on their own social outlets.)

Receptions are a different animal: Most couples intend for the reception to be a full-on celebration, rather than a sacred ceremony, so the rules loosen up a little bit where social media is concerned—unless the couple has requested a phone-free zone, and then you must respect their wishes. A wedding hashtag, on the other hand, is an invitation for guests to document the evening and share it on social media in real time, if they so choose. It’s a way for the newlyweds to relive the night long after the wedding is over, and they’ll appreciate seeing all the funny little moments they might have missed in their deliriously happy fog of marital bliss.

But even if there is a wedding hashtag, it’s most polite to skip the photos and videos of the cake-cutting or first dances, as these are special moments that are best left uninterrupted. if you simply cannot live without a photo of the moment (or the bride has mentioned she’d love for you to sneak a photo of her father-daughter dance), be sure to take it as discreetly as possible: phone low, flash off, and far out of the way of the photographer.

The rest of the reception is fair game, so long as you are being respectful of the couple, the photographer, and other guests. Do not capture any moments that might be embarrassing or revealing for anyone in attendance, and should you unintentionally capture an embarrassing or revealing moment, delete it and carry on with your life.

In short, be respectful when taking photos and considerate when posting them. Turns out that old Golden Rule applies to Instagram, too.

WATCH: How to Address Wedding Invitations

While guests need to be up to speed on etiquette matters before attending weddings, the bride and groom have a lot to learn before they take a trip down the altar, too. Here, our guide to addressing wedding invitations so that every happy couple can properly mind their p's and q's.