Gentlemen! Before you tumble headlong into a vortex of twin tuxedos and tasteless displays of wealth (invite me!), here are a few sartorial suggestions.
Start by considering how formally or informally you plan to dress (you and your partner can argue about this for ages if you like) and how much money you're willing to spend (this too!). Once you've settled that, there's a gay world of options, from a stiff haunted wedding gown from Goodwill ($18) to the latest designer suits at Barneys ($1,095 and way up).
Don't want to be bothered? That's cool. For a fuss-free, moderately priced suit or tuxedo rental, save yourself time and agony—go to Men's Wearhouse, answer a few questions, and let them do their jobs. These people are pros and will make things as painless as possible for the shopping-averse. They will put you together down to the last detail, and you will be appropriately dressed at whatever level of formality you require. Done and done.
If you want something more individual, but don't feel confident doing it on your own, this next idea can work with budgets from economical to astronomical. Shop with a friend who knows about clothing and has nothing to gain from making you look like an asshole. Your friend can make suggestions, look at your ass from behind, and help coordinate the shopping between stores and multiple salespeople. Buy things you'll wear again. Buy your friend's lunch.
For the gay that wants a completely original look, the only limit is your sick imagination. Find a local artist/designer who will work with you to make your idea a reality. In Seattle, Michael Cepress makes creative tailored looks for men and has a great sense of color (michaelcepress.com). My work runs the gamut from opulent gender-blending extravaganzas to custom-printed jeans (itsmarkmitchell.com). Let your freak flag fly. There are creative people in every city working in custom clothing. Find one you like and support their work! Book early, as custom work takes time, and you can be the special snowflake of your dreams.
While I long to see over-the-top drag weddings and boy-brides in Balmain marrying withered sugar grampas, most people will keep it fairly simple. So here are three final easy-to-follow suggestions: Be somewhat comfortable, whether you're wearing a natty suit or an art project you've crafted from popper bottles and porn—avoid being trussed-up and unable to pee, unless that's your intention. Next, no matter how casual you and yours agree to keep things, look as though you made an effort. Here in the Great Northwest, things are drastically easygoing, but at least show up looking like you meant to be there. Finally and most importantly, don't waste much energy worrying about pleasing anyone but your beloved. Be and look your best for them, and the rest will take care of itself.