I have rashly undertaken to organise the cake for the joint 5th birthday party for my DD and 2 other friends.
I was thinking of something along the following lines:
Round sponge to create a princess face
cut off a bit on the side, and have triangle sponge attached, to create a princess hat.
Something to create hair at the side.
Ice and decorate to make a face, tiara or some such (details a bit hazy), and decorate the pointy princess hat.
Was thinking of using royal icing (get it?) for the icing.