Wedding season is here—and if you’re like us, you’re probably already planning what to wear to the ceremonies you’ll attend in the coming months. While weddings have become more relaxed in recent years, that can actually make choosing an outfit trickier: nobody wants to look too casual or too formal for a friend’s special day.

“The best wedding guest outfits find that sweet spot—stylish and put-together without being overdone or clashing with the dress code,” says Rosie Williams, co-founder of bridal brand The Own Studio, which recently expanded into evening wear. “Even though dress codes are more flexible now, making an effort still matters. It shows the couple you respect their day and understand its importance.”

Of course, many old-fashioned rules no longer apply. Wearing black is perfectly fine, and despite the old myth, red doesn’t mean you’ve had a fling with the groom (though it’s best avoided at some Indian, Pakistani, and Chinese weddings, where brides traditionally wear red).

Still, there are some unspoken guidelines on what not to wear. Here’s what the experts say to steer clear of:

### White
Unless the couple specifically requests it (like for bridal party attire), avoid white. Printed white dresses fall into a gray area. “They’re usually discouraged, but context matters,” Williams says. “When in doubt, check with the couple.”

### Pale Colors
Sydney Sweeney’s light blue dress at a wedding sparked debate when some online critics said it looked too close to white in photos. “Anything very light that photographs white isn’t worth the risk,” Williams advises. Stylist Cassie Walker Graham adds that pastel pink or champagne shades can sometimes overlap with bridesmaid colors, so it’s worth checking with the bride first.

### Super-Short Minis
For formal or religious weddings, a super-short hemline is a bad idea. But for more casual events, a chic minidress can work—if styled thoughtfully. “Pair it with elegant flats, a tailored blazer, or bold accessories,” Williams suggests. “A short dress doesn’t have to look cheap—it’s all about the fabric and fit.”

### Low-Cut Dresses
Deep necklines are usually best avoided, but it depends on the wedding. “Consider the couple, venue, and overall vibe,” Williams says. “When in doubt, err on the side of modesty.”