Once the cake has baked and is out of the oven I try to leave it until the next day before I start working on it. This gives the cake plenty of time to cool thoroughly and ‘settle’, making it easier to slice and carve to shape if needed.
While it is cooling, if the cake is to be covered in coloured icing rather than white, I will prepare the coloured fondant. I like to do this the day before I’m going to use it as it allows the colour to develop (especially important with dark colours). Adding colour can also soften the icing or make it sticky so allowing it to rest overnight makes it easier to work with again.
The next step is filling and crumb-coating the cake. This is something I’m improving on all the time. Its not a step that can be rushed. If the cake is being filled with buttercream I like to put it in the fridge once it is filled to allow the buttercream and cake to firm up. Once firm I’ll add the first crumb coat, then the cake is back in the fridge to allow that to firm also. Sometimes I’ll add a further cover of buttercream if I feel the cake needs it but I find that can cause problems. If when covering with fondant the buttercream gets too warm it causes the icing to sag and bulge at the bottom of the cake. I have looked into a few ways to solve this problem, I’ve yet to test them!