Aim for a look that’s shipshape by using shades of blue from periwinkle to navy, a motif like a compass or a knot, or a rope tied around your invitations. A combination of custom calligraphy and illustrations are letterpressed on white card stock, by Karen Bartolomei for Grapevine, grapevinepaperie.com. Enclosure cards in staggered heights tuck away into a wave-shaped pocket. To add to the nautical feel, the invitation is tied with periwinkle silk cord, $6,000 for 100 sets. For a subtler look, use a classic combination of navy and white, like the triple-layered invitation ensemble enclosed in a deep-blue pocket folder, $2,100 for 100 sets, from On Paper Press, onpaper.com.