Things You'll Need
Instructions
Draw vertical lines with the ruler 1 inch, 10 inches, 12 inches and 21 inches from one 12 inch-long side of the poster.
Divide each 9 inch-long section of poster into six segments, 1-1/2 inches wide each, with five vertical lines.
Draw a triangle in each 1-1/2 inch wide section that is 1 inch wide and 5 inches tall, centered across the width of each section, with the 1 inch-wide edges of the triangles running along the bottom edge of the paper.
Draw a triangle in each 1-1/2 inch-wide section that is 1 inch wide and 5 inches tall, centered across the width of each section, with the 1 inch-wide edges of the triangles running along the top edge of the paper. The triangles in this row should face the other row, with two inches between them.
Trace over the vertical lines from Step 1 and the triangles with permanent marker.
Erase any pencil marks.