This is a simple but effective way of decorating a cake, I just used these and nothing else on my cake & it looked lovely, you could add piped or painted flowers to make it more suited to an adult (mine was for my daughter).
1. Make royal icing in your desired colours, this recipe is fairly close to the one I used http://allrecipes.co.uk/recipe/6350/royal-icing.aspx
2. Draw your templates out and place under a sheet of baking parchment or cellophane. Using a piping bag fitted with a number 2 nozzle pipe your outlines.
3. Let down your firm icing with a little water or egg white to give you icing of pouring consistency, put this in an icing bag fitted with a number 3 nozzle and flood your outlines.
Or you can wait until they're dry and pipe detail on like this
Fold a large piece of card like a fan and line it with baking parchment. Pipe thick lines down the creases and push your wings into each line.
I will post the pictures of the finished cake soon xx