Also any tips for rolling out and being able to land smoothly on the cake?

You can use vegetable shortening (Copha) or icing sugar (sparingly) to help make it easier to roll, but your best bet is a pastry sheet if you have one, or baking paper. To get it on the cake, you will need to roll it over the rolling pin, lay it on and unroll it. Again, YouTube is your friend for this.

Your buttrcream can also be made in advance, if it makes it easier.