Weddings these days have fewer and fewer fashion rules than in decades past, which can be great, but also makes things a tad more complicated. Many of today's brides are passing on traditional gowns in favor of elegant pants or jumpsuits, the occasional groom skips the typical black tux for a pastel suit, and even bridesmaids are ditching the cookie-cutter dresses for something they can wear over and over again. This means guests *also* have just as much freedom with their styles.

But before you whip out any outfit and call it a day, there are a few things to remember while getting dressed in order to still be respectful of the ceremony and the people getting married. Some of the rules are pretty straightforward and easy to follow (e.g., what colors to avoid), while others require a little more outfit planning—like figuring out what the heck "semi-formal wedding attire" means.

To make sure you really nail it on the big day (well, not *your* big day, but you know what I mean), we tapped Elaine Swann, lifestyle and etiquette expert and founder of The Swann School of Protocol, to give us the low-down on some spoken and unspoken fashion rules.

Keep reading for her advice about about what not to wear to a wedding, plus some stylish ideas about what you should wear instead. After this, you'll be ready to handle any dress code request that's thrown your way. Promise. Also, we've got you covered with more wedding guest dresses and what to wear to a rehearsal dinner!

1. Avoid wearing white...or white-ish colors!

I'm talkin' off-white, light yellow with a white lace overlay, or really, really pale blue. Swann says that lighter colors tend to photograph white, and knowing how your look will photograph is just a general thing to be aware of, BTW. Avoiding white should be a no-brainer, but it still bears saying—unless the bride has specifically requested that guests wear it.

Want to wear something close to white? Try a neutral!

2. Try to stay away from the bridal party's colors (if at all possible)!

Swann recommends that you stay away from colors that match the wedding (unless otherwise stated) so you don't look like you're part of the bridal party. How can you determine this? "You can tell what the color scheme for the wedding is from the invitation or the wedding website, which gives an idea of what direction the couple might be going." If you're still unsure, you can always ask the bride or a bridesmaid!

3. Consider the season!

Aligning your look to the temperature is key for fitting in with everyone else and also feeling comfortable. Think: thicker fabrics like velvet for winter, florals for spring, and lighter fabrics, like cotton and linen for summer.

4. Lean towards dressing up, even for "casual" weddings.

Even if the wedding has a more low-key dress code, I promise you: It is not that casual. Meaning, stay away from sweats, shorts, jeans, T-shirts. "If you have to choose between being underdressed or overdressed, it's always better to be overdressed," Swann explains, paraphrasing the classic idiom.

But she also insists that if you are truly baffled by the dress code and have no idea what to wear, you should absolutely reach out for help. "I encourage people to embrace that awkward moment and ask for an example from someone in the wedding party, whether it's the bride, the groom, or the bridal party."

If you are looking for something that skews more casual but is still fit for a wedding, go for any of the simple yet stylish outfits below, which can easily be dressed up or down.

5. Zhuzh up your pants.

So you wanna wear pants? Totally fine! Just make sure they still seem dressy enough. Start with tailored trousers and a polished blouse, or make things easy for yourself by grabbing a matching blazer. Pantsuits are a great way to go, or you can coordinate the color of your pants with your top and have a monochrome moment.

6. Cover your shoulders, if applicable!

Is the ceremony taking place in a church or in an institution with a more modest dress code? Swann says, above all, it's important to remember that weddings are a sacred occasion. Be respectful of where the vows are being exchanged, and you can always bring a shawl or sweater to cover yourself.

This simple ribbed cardi would do the trick.

7. Keep an eye on your neckline!

"You certainly don't have to wear something that is old fashioned—you can stay on trend," Swann says. "But, remember that part of the wedding itself may be a very religious occasion as well, so there is some modesty that could be expected."

Not saying don't do a deep V, just don't be asking "how low can you go?" Here's a plunge that should still work.

8. Go for subtle statements.

People love to say, "Don't outshine the bride." But, in my opinion, it's really hard to do that. Everyone knows who the spotlight is supposed to be on, so you should feel free to wear something you think is really special, even in a bold color or silhouette.

That being said...don't show up in another wedding dress! Or something else you know will pull eyes in photos later on. Just keep the event at hand in mind—as long as you think your outfit will be on par with everyone else's (just a little more fabulous, because they wish), you should be good. "There's a difference between wearing a cocktail dress that's really cute for the club and wearing a cocktail dress that's meant for a wedding," Swann explains.

9. Go for understated sparkle!

Unless it is a black tie event, it's all about lowkey glitz and glam. Instead of over-the-top sequins, try low-key crystals or other textures like ruffles, lace, or plissé for a look that stands out, but doesn't mimic a disco ball.

10. Keep the dress code in mind.

Read the room (or, um, the invitation): Don’t wear a tux or a ballgown to a backyard wedding—in that case, it’s better to keep it a little more low-key.

Swann also says the location is a big clue for what you should wear. "For example, if it's a destination wedding, then you know that you'd be wearing resort-style attire," she says. "If it's going to take place at a high-end hotel, then that'll give you an idea of the theme."

The other indicator that helps determine your style is the time of day the ceremony is taking place. "Earlier in the day, you're going to find that the attire is going to be less formal, which means more bright colors and flowy fabrics. Later in the evening is when you'll get to that formal attire where you have black and gold hues, beads, and sparkles." Of course, this is all generally speaking, but these are good guidelines to follow.

If you've got a garden wedding you're attending this spring or summer, here's a cute option!

11. Save the rips (even intentional ones!) for another occasion.

It's usually wisest to save anything super distressed or with frayed edges for other occasions. But if you like the idea of showing a little unexpected skin, consider a stylish cutout. As Swann points out, you don't have to completely forgo trends, either.

This style is the perfect mix of trendy yet appropriate. Plus, the breezy linen material will keep you cool during an outdoor ceremony.

12. Be strategic about your choice of shoes.

Comfort is important, especially if you plan on turning up on the dance floor. But wearing flip flops to the ceremony? Probably not the move, unless it's a casual, toes in the sand beach wedding. If you know there is going to be a long walk from one point to another throughout the festivities, Swann says comfy flat shoes (flip flops or otherwise) that you can slip in and out of quickly might be good to bring—but only for those in between moments!

Also, if any part of the day is happening on grass, Swann suggests wearing wedges or shoes with a wider or flared heel so you won't sink in the ground when you walk. "Get that information in advance, and don't feel as though you're bothering the couple or bothering the party by asking these sorts of questions—they want you to be comfortable," Swann says.