Diamond cutters are a great way to add a diamond pattern to a cake. They can be purchased from Global Sugar Art online and only cost a few dollars a piece. You can purchase a simple diamond pattern or a double diamond. This creates a small diamond inside a larger one.
If you are using it on fondant you can press it gently as soon as the cake is covered.
For buttercream it must crust first. Gently press it into the cake and continue around until completely covered. If it is used before the buttercream crusts the frosting will come off onto the cutter.
Add dragees or flowers inside the diamonds or at the crossing spots.