1.Secure cakes, long sides together, on 30cm x 40cm (12-inch x 16-inch) rectangular cake board with a little frosting.
2.Reserve ½ cup of the frosting; tint remaining frosting green. Spread green frosting over top and sides of cake.
3.Tint coconut green; press over the top and sides of cake.
4.Divide store-bought icing in half. Knead half the icing on a surface dusted with a little sifted icing sugar until icing loses its stickiness. Tint remaining icing yellow; knead on a surface dusted with a little sifted icing sugar until icing loses its stickiness.
5.Roll yellow icing into a rope shape about 60cm x 5mm thick. Repeat with white icing. Twist both icings together; gently roll to secure together. Cut a little round from each end of the rope, flatten slightly; reserve.
6.Place sprinkles in a shallow bowl. Spread the remaining frosting all over both rollettes; roll in sprinkles to coat.
7.Using picture as a guide, position rollettes on the cake to form skipping rope handles. Position rope on cake, gently pushing into the end of each rollette; attach the flattened icings on the other side of the rollettes to form rope knots.
Use hundreds and thousands as an alternative to the orange sprinkles. You can use cream-filled rollettes, if you prefer. If using butter cream instead of the vanilla frosting, you will need two quantities. White icing is also known as fondant (it’s the traditional icing used on wedding cakes). It is available in packets from the supermarket and cake decorating shops.