Going with the under the sea baby shower could be the coolest (pardon the pun) baby shower theme you'll ever have!
To start, you could use the under the sea baby shower invitations that are available commercially. Choosing those would really free up time for you and take much less effort. But if you don't find one that you like, you can easily create one using an underwater photograph or illustration found on the internet.
The under the sea baby shower color scheme would definitely have to be in blues and greens. Set the ambiance of the baby shower by giving the room a watery feel by changing the light bulbs to blue and green. Suspend artificial fish and clear Christmas balls from the ceiling at various heights to make it appear that you're walking underwater. Tent the room with various shades of blue fabric to simulate waves. Have blue and green balloons floating in bunches around the room, but arranged so they look like bubbles rising. Create several styrofoam “coral” cutouts and stand them up near the balloon bubbles. Finally, using tulle and koosh balls on the floor, simulate brain corals and sea anemones.
Cover the tables with a light blue fabric and use a piece of fishnet as a centerpiece base. Set a goldfish bowl on top with aqua-tinted water, glass pebbles, and white chrysanthemums to simulate sea anemones. Scatter a few seashells around and intersperse them with some votive candles in glass-green votive glasses. Sprinkle a few glass pebbles around to catch the light.
Order an underwater printed background for your buffet table or have different shades of green and blue tulle attached to the ceiling and flowing down behind the table. Pin a few fish onto this and also some large silver sequins to serve as bubbles. Set the buffet table with a blue-green cloth and use aqua serving dishes or shell-shaped dishes for the food. Have a few fish “swimming” among the food platters. The cake is your centerpiece here, so set it high above the other food with some clear glass blocks.
For the food, baked fish sticks on a base of wavy green lettuce salad with a green goddess dressing, spinach and plain spiral pasta to mimic seaweed topped with a marinara sauce, and crab cakes make a great meal. Dessert could be blueberry french macaroons, a blackberry mousse, or even sand-colored vanilla cupcakes topped with a blue icing and gummy fish. For the drinks, a blue Kool-aid punch, blue Gatorade or simply Sprite or 7Up with a few drops of blue food coloring make a splashingly watery drink. Add a few ice cubes that have gummy fish frozen into them and you've got yourself an Ocean Breeze. If something alcoholic is desired, blue Margaritas or Blue Hawaiis are perfect.
Favors definitely have to have that sea influence. A beautiful
seashell, an ocean-scented blue candle, and a collection of fish
and seashell soaps would look wonderful in a small fisherman's basket.