Dotted lines indicate scoring marks (cutting only about a 1/3
of the width of the paper) in order to weaken the paper
and help bend it in the correct direction.
Red dotted lines (----) indicate mountain folds and
therefore the scoring should be done on the front or
white side of the paper.
Blue dotted lines (-・-・-・) indicate valley folds so the
scoring should be done on the printed or backside of the paper.