Does anyone know the correct way to frost & tier cake layers? I only do 2 and put frosting in between. It usually ALWAYS "bubbles" out even when I use a crusting buttercream.... What can I do?? Do I cut many thin layers??

If you're filling the cakes with a very soft filling, you'd want to pipe a "dam" of stiff buttercream around the cake, about a half inch in. If it's the kind of filling that could seep into the cake, you'd want to frost the top of one cake and the bottom of the cake above it with a very thin layer of butter cream, then dam it. After filling and stacking, cover the cake with a thin crumb coat to seal in the crumbs, then cover loosely with plastic wrap and let it sit at least 3 hours or overnight. This allows the cake to settle and settling is what prevents bubbles from happening. Some people like to put a weight on the cakes on top of the plastic wrap. It would be something slightly heavy and very wide and flat, for even weight distribution. Some people like to use ceramic floor tiles and some people like to use books. Some people don't use a weight at all. Hope this helps you.