If you are feeling very ambitious and would like to add more detail to your Hearst Tower model, you can cut out the corners to match the angled corners of the real building.
Before scoring or folding the tower piece, cut out the sixteen diamond shapes located at the corners (you'll have to splice together the diamonds from the left and right ends of the piece as well). Be careful to leave a little paper holding the corners of the building together.
Next score the diamonds horizontally on the back and fold each forward to match the angles of the cut corners. Glue the roof of the tower in place to hold the tower in a sturdy rectangular shape. Then place a little glue on the edges of each diamond piece and use a long tweezer and toothpick to place each in the correct position inside the walls of the tower.