Etiquette tips for paper pleasantries.

Few pre-wedding details are as traditionally regimented as the wedding invitation. Guidelines about formal titles, invitation pieces and included information are one of the few customs that modern weddings haven't thrown out the window, and they can be overwhelming to the inexperienced. Here are a few tips on how to navigate the often-confusing realm of invitation etiquette.

DO: Match your invitation style to your event.

Your wedding invitation often acts as your guests' first glimpse into what's in store for the big day. Set the tone with wording, design and details.

Stationers can guide couples through the nuances of envelope liners, monogrammed bellybands and other design elements to ensure a polished and coordinated invitation suite. But be wary of going too far, even with ultra-formal events. “Decorative extras can add up, so pick your priorities and set a stationary budget,” advises Sarah Nugent, owner of You're Invited.

Another stylistic choice is how to address envelopes. It's fine to use preferred names for most wedding styles, but use formal honorifics—like Mr. and Mrs. John Doe—for a formal event.

DON'T: Include registry information.

One firm etiquette rule has stood the test of time: Never, ever include registry information on the invitation. “The focus should be on your guests and not the gifts,” says Nugent. “Listing your registries implies that a gift is a requirement for attendance.” She suggests instead including registry information on your wedding website and asking friends and family to spread the info via word of mouth.

DO: Include the important details.

Regardless of your wedding's style, you'll need to include information on who's getting married and when and where it's taking place. Other details you may want to include, depending on your event, are suggested attire, transportation and hotel information, activities like the cocktail hour or after party and a link to your wedding website.

Your suite also must include a way for guests to RSVP. It can range from a traditional card (with pre-addressed and -stamped return envelope) or a link to an RSVP website, based on your wedding's formality.

DON'T: Wait too long to mail your invitations.

Plan to mail your invitations six to eight weeks before your wedding (10 to 12 weeks for guests who live in another country). Your RSVP deadline should be about two weeks before your big day. If in doubt on when to send, always allow for more time and mail your invitations earlier rather than later, especially if your wedding falls near a major holiday.