Dust the 30cm drum with icing sugar and sprinkle with water. Knead a third of the pink sugarpaste until pliable, then, on a surface lightly dusted with icing sugar, roll out into a circle slightly larger than the top of the drum and about 3mm thick. Wrap it loosely around the rolling pin and lift on to the drum. Smooth with your hands. Trim away any excess overhanging the sides and reseal it in the bag. Leave at room temperature overnight before decorating.
Lightly dust a clean, flat surface with icing sugar. Roll out both the remaining pink sugarpaste blocks, one at a time, into circles about 5mm thick and slightly larger than the diameter of each cake, its sides and drum. Wrap each circle loosely around the rolling pin, place it over the cake and gently smooth with your hands. Do not stretch the sugarpaste, and work quickly, as it will dry out. Cut away any excess at the foot of the drums and reseal it in the bag. Take a large knife and roll it gently along the top surface of the cakes, scoring lines to form a criss-cross (each line about 1½cm apart) to resemble quilting. Push a dragee in where the lines meet. The centre of the bottom tier will not be seen, so no need to use dragees. Leave overnight.