Anycake too large to hold in your hand must be frosted on either a counter or a turntable. You proceed as for smaller cakes, frosting first each side separately and then the top. Finish the sides by placing the edge of the cake parallel to the counter edge. Rest your spatula perpendicular to the edge and draw it against the cake’s side with a steady stroke. The counter edge serves as your guide. Slip the spatula under the cardboard, lift, and turn the cake to finish its other sides in the same way. Then smooth the top as previously directed.