I need to make a two tier all Swiss buttercream cake with one tier white and the top tier black. I’m planning on airbrushing the top tier black, but I don’t know how to move the layer (once it has been airbrushed) to put it on the top. Any advice will help greatly. Thanks 

if you got the bottom tier real cold -- you could cover it with waxed paper and then spray it all stacked up --

or you could spray it separate and stick a dowel down into the center and out of the top of the cake and pick it up that way -- from the bottom and then hold the handle -- just gotta cover the hole -- or spray it afterwards