You're going to a wedding, not a meeting at the office!
Drop the business persona and show your style in a skirt, dress or any kind of clothing that would look out of place with a coffee stain. This is a celebration of two people choosing to unite their lives together forever, so the least you can do is find something that isn't overly stuffy and businessy to wear. We're not just talking about your standard black or charcoal suit. This rule also applies to pretty pastel skirt-jacket combos. They might work for a dinner event, but they just set the wrong tone for weddings.
Yes, we know some very powerful women frequently wear pantsuits, but even Hillary Clinton wore a vibrant dress on Chelsea's big day, and if she can do it, you can, too.
We'd also advise staying away from businessy accessories -- trade the giant bag or briefcase for a clutch, and don't wear any scarves that scream "I belong in cubicle No. 4!"