I mean typical Nautical theme is going to be anchors, fish, shells, and colors of navy blue and white.

Or the pink of the inside of the shell and the blue/gray of the ocean.

Other sand colors involve sea grass and sand/beige. You could be using salt and sand in your centerpieces. Lanterns or lighthouses.

There is really a lot you can do. I had a tropical theme and I used tiki torches, burning outside and inside with long grass stuck in the top. Pictures definitely set the scene. You can either use pictures of the two of you on the beach or big posters of beach scenes. You could also go write in the beach and take pictures of that. Consider writing your names, I love you, and quotes from the movie. There are lots of photo collages you could make of those shots or borrow 8×10 picture frames from everyone you know and use those beach shots and the frame as your centerpieces. Maybe even see if you can find a shot of the wooden rowboat like they had in the film and since WWII was a crucial part of that movie, that famous photo "August 1945"

Really there is so much you can do with a beach theme and with the movie. Think about what colors you really like and what you think of when you think of your wedding.
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