Two big fashion rules endure for women going to weddings these days.

First, don't wear white. Not off-white. Not cream. Not even eggshell. It's the bride's day, and she gets to wear white.

And second, save the flashiness for the club. Showing too much cleavage, belly or leg might be the Hollywood-driven standard for evenings out these days, but it's still not appropriate at weddings.

All those other well-intentioned rules your always-appropriate mother might have lived by? Most are being tossed aside like a pair of well-worn pantyhose.

Once the mother of all rule-conscious fashion events, the wedding has joined the ranks of Sunday church services and funerals in shedding some of its strict decorum for what's acceptable, according to stylists and dress store owners.

"You're going to see everything at weddings now," says Kathleen Fisher, an owner of Anne Crawford Custom Shopping in Raleigh.

A short dress? It's fine for an after 6 p.m. outdoor reception in June.

Cotton jersey dress? Why not, especially if you're invited to a destination wedding somewhere warm.

The little black dress? How stylish, even if it's not a Manhattan wedding.

Flip-flops? Sure, if it's a beach wedding.

With more weddings on Friday night or Sunday afternoon, at the beach or somewhere tropical, seemingly anything goes. For today's wedding guest, it's more about being chic and feeling good rather than chic and proper.

"Your number one goal is to be comfortable," says Cynthia Nellis, the fashion expert at about.com.

Of course, what you wear should be dictated by the event itself. If the invitation says black tie and the ceremony is at 8 p.m., you'll want to wear your most formal look. If the wedding is on the beach, you won't want to wear your expensive Jimmy Choo pumps in the sand.

It's hard to know

The invitation and, increasingly these days, the couple's Web site typically set the tone for the wedding and style of dress. But if it's a 6 p.m. outdoor wedding, it's a harder call and one that seems to trip up even the most fashion-conscious.

Rebecca Black, an etiquette specialist who is a moderator at topweddingquestions.com, says overwhelmingly the most questions she is asked on the site are about what to wear to a wedding.

"We are more casual than we used to be," she says. "Everything is an informal affair now until you are told it's formal."

She said part of the reason for all the wedding-fashion confusion is that younger generations didn't grow up with strong role models on appropriate dress for certain events. Even some baby boomers, who might have grown up with parents who were rule-conscious about dress, might have thumbed the rules early on and are now at a loss for what's appropriate.

But even she acknowledges that many of those old rules are gone, which only adds to the confusion.

Most stylists says today's good wedding style takes into consideration common sense and respectfulness. Part of that common-sense approach begins with fabric choice, Nellis says, especially if the wedding or reception is going to be outdoors this spring or summer.

If the weather is expected to be hot and humid, consider a dress in cool cotton pique or a breathable, tissue-weight linen. If the wedding is more formal or dressier, you can still get away with cotton, Fisher says. "Cotton fabrics are so much better than they used to be."

Find a cotton dress with a sateen finish or one with a jacquard print. Or even go with a cotton sundress and dress it up with on-trend accessories, including a pair of wedges and a clutch, Fisher says.

Don't rule out dresses in chiffon or a cotton blend that are comfortable, move with you and don't stick to your body.

"There are a lot of options beyond T-shirt material," Nellis says.

Not too hot or too cold

Strapless cocktail dresses have become another popular summer wedding choice, especially for dressier events. But make sure to take a wrap or a light scarf to cover up in the church or keep you warm as the evening gets cooler.

You might want to pass, however, on a dress or skirt with a lining to avoid being too hot at outdoor wedding functions, Nellis says. And be sure to consider what undergarments a certain dress might require. If you need to wear shapewear, such as Spanx, with a certain dress, you might want to choose instead a looser-fitting dress or one with a less restrictive cut to avoid being too hot.

Also consider color when choosing wedding wear. It might be tempting to wear a stylish new white dress to a wedding. White is, after all, one of this spring's more popular colors.

But don't do it, says Eliza Stoecker, an owner of Fleur, a women's clothing boutique with stores in Raleigh and Chapel Hill. "That's the only rule that's still valid in 2008," she says.

If you do want to wear white, save it for the rehearsal dinner.

Black also encourages guests to avoid wearing red to weddings because it's such a bold color.

But black is OK

Fortunately, you can choose from a wide variety of other trendy colors this spring, including yellow, kelly green, cobalt blue, tangerine, turquoise and raspberry, all of which are wedding appropriate. Even black is appropriate for weddings these days, especially if it's a more formal wedding, Stoecker says.

Black said she remembers when wearing black to weddings was considered taboo. When a mother wore black to a wedding, it was a statement that she didn't approve of the match, Black says. Now, some brides are dressing their bridesmaids and even both mothers in black. But keep in mind the temperature outside. Black tends to be hotter than a lighter color, Nellis says.

"The challenge is that we count on certain things, like a black dress or Spanx, to help us look thinner," Nellis said. "That all goes out the window with this."

For slimmer looks, instead try a two-piece outfit, a dress with side ruching or an A-line dress.

"Get a great color that really flatters your skin," Nellis says. "That forgives a lot of sins."