Before your wedding -- typically the day before -- friends and family gather to rehearse for the ceremony, then gather for a meal after. Occasionally, out of town guests or others who are important to the wedding couple, but not a part of the ceremony are also invited to this dinner. Send out an invitation in the style of the wedding or the party, including everything the invitee needs to know.
The rehearsal invitation needs to include the hosts' names, the reason for the celebration, the party location, the time and a way to RSVP. For example, the invitation might read, "Mr. and Mrs. Randall Gustafson invite you to the rehearsal of the wedding ceremony of their son, Jeff Gustafson, and Aimee Morris, at St. John Episcopal Church in Rochester, NY. at 4:30 p.m. Dinner to follow at Mario's. Regrets only to 555-845-6852." If guests are not as familiar with the area, include specific addresses to make the locations easy to find.