Cut out the main part of the building. Score and fold the inner tabs down. Fold the walls down and glue the tabs at the corners.
Cut out the two colonnades and fold the sides. (Note that the outer tabs are reverse or valley folds scored on the back, while the inner folds are mountain folds scored on the front of the paper.) Glue the colonnades to the walls of the building, with the tabs tucked inside the wall.