NOT KNOWN FACTS ABOUT RAINBOW CAKE AT WOOLWORTHS

Undecided how for making lavender sugar (I would like to have the floral equilibrium ideal). I have both clean lavender and 2week aged dried lavender from my back garden atm. How do I prepare lavender sugar?When the tops of your rainbow cake layers are domed, then use a serrated knife to chop off the best of your domes in order to stack them evenly