I got this idea from another Baby Shower Cake I had seen and decided to try it. I already had a soccer ball cake pan so I used it to make the belly. I bought a Pyrex ingredient bowl for the breasts.
The cake is white cake mix. I used homemade buttercream and covered the entire cake, but you can use any icing you want. After icing the cake I colored store bought white fondant in skin and baby pink. I covered each breast with the skin colored fondant and trimmed the edges. Then I rolled out the rest of the white and covered the bottom half of the breasts and then the belly.
Normally, you would smooth the fondant to hug the cake, but I let it fall naturally around the belly to resemble a dress. With the pink fondant, I rolled it out flat and cut it into one long strip, 3 medium strips and one small strip. I used the long strip to wrap under the breasts, then fashioned a bow with one of the medium strips by creating a ring, pinching the middle together and wrapping the small strip around the pinched middle. Before adding the bow to the middle of the sash, I used the last 2 medium sized strips to create the ribbons under the bow, then added the bow on top.
All the fondant can be attached using a light brushing of water. The water will act like a glue for the fondant. Everyone loved it!