1. Don't Reinvent the Wheel
Most important: Look and feel like yourself. "Your wedding day isn't the time to make an unexpected sartorial statement," says Dan Rookwood, the United States editor of MrPorter.com. Avoid overly trendy items like collar bars, skinny ties, or satin cravats-unless they're a signature part of your everyday style.
2. Go for Tried-and-True Colors
No one ever regretted walking down the aisle in gray, tan, navy, or black. These shades are universally slimming, photograph well, and won't clash with the bridal party-whether they're wearing hot pink or cool blue.
3. Wear the Right Weight
Cooler weather calls for heftier fabrics like wool or cashmere, but if you're getting married in the summer or where it's hot and humid, light fabrics like linen, khaki, and seersucker are a must. "Just be sure to keep the fit slim," says New York City stylist Mark Holmes. Bulky or billowy lightweight textiles look sloppy and informal.
4. Diamonds are Forever-White Button-Ups Aren't
"The best white shirt is a new one," says Rookwood. Spring for a cotton poplin spread-collar version with French cuffs, or mother-of-pearl buttons. For a custom option that doesn't require any fittings, SuitSupply.com offers a range of cuts and fabrics starting at $149.
5. Suit Yourself
The perfect cut for a former linebacker is unlikely to work for the lead singer of an indie band. Wide lapels tend to flatter the former (Tom Ford makes a great version), while the latter looks best in a narrower silhouette (YSL is a good option). "Most of us are somewhere in the middle," says Holmes, who likes Burberry London's cut.
6. Give Groomsmen a Bro (Dress) Code
Your best friends aren't clones, and it's unlikely they'll feel comfortable in the same suits. Instead, set clear standards for elegant variation-like asking everyone to come in a black tux or navy suit-and add a cohesive accessory, such as a matching tie or pocket square, says Rookwood. One note: Shirts and shoes should coordinate, so be specific about the color for each.
7. Know the Bottom Line on the Bottom Button
The lower button of a two- or three-button suit is always left undone. Read that again-it's a fact that's easy to forget, yet never changes. "If it's a one-button suit, do it up," says Rookwood. "If it's a four-button … you might want to consider a different choice for this occasion."