I have a friend who wants a cake in the shape of a shoe or a cake with a shoe on the cake.
There is a 3D chocolate mold of a shoe you can get. You can make the shoe out of chocolate or fondant and place it on top of the cake. Just a suggestion. Good Luck!
Another way to do this is to start with a picture of the shoe, if she wants a particular style, and use that as your guide. Bake a basic sheetcake or smaller and once baked, freeze it for a little bit to firm it up. Then, witha sharp knife, start sculpting away until you get the desired shape of the shoe. Cover it with regular icing or fondant, your preference, and then embelish it from there! Happy baking, Missey PS-Be sure to post a picture for us to enjoy!