Painting The Gown
Dilute the same food colouring you used to create your aqua cake layers, and dilute it with a little bit of clear food grade alcohol. Begin by painting a dark layer around the base of the cake. Dip that same brush in another bowl containing only food grade alcohol, and begin to brush that dark line of colour up the cake, creating a lighter shade. Continue this process, blending and fading your colour upward until entire cake is covered. Set aside to dry.