Store buttercream icing in the refrigerator in a container. However, don’t make buttercream in advance, as it is best to use it as fresh as possible. If you have kept it in the fridge for any length of time, let it warm to room temperature before using it.
If your buttercream icing is too thick you can use evaporated milk or warm water to thin it down. Use the liquid sparingly and mix it in with your icing spatula. You can thin chocolate buttercream with a little hot coffee or hot water.
Don’t forget to sprinkle toppings on white the icing is still wet, otherwise they won’t stay put.