First have a calligrapher write out the bride's and groom's names and a message, then have the writing made into rubber stamps. The boxes come flat: Stamp the lids as shown; let ink dry overnight. Poke a small hole in the center of the lid with an awl (available at hardware stores). Fold box and lid. Slip bird's foot through the hole.
Spring Favors: How to Make the Bird Boxes
Martha Stewart Weddings, Spring 2005