Don't let the sharp corners of a square cake intimidate you. It's easy to use your hands to shape fondant around the corners, so you finish with perfectly smooth edges.
Prepare cake by lightly covering with buttercream icing. Position fondant on cake, smoothing the top with the Easy-Glide Smoother. Pull the corner flaps gently out and away from the cake; smooth the corners with hand to eliminate the creases. Smooth sides with Smoother.
Trim off excess fondant at bottom with a spatula or sharp knife.
To give a finished look, smooth top, all sides and bottom edge of cake again with the Smoother.