Step 1: Peg Bar Assembly
Center and glue ruler to the edge of plexi sheet lengthwise. The dowel pins are beveled on each end. Cut or sand one end flat. Glue the pins into the ruler's binder holes. Once its dry, the assembly is ready to use.
Step 2: Suggested Use
I use 3-hole punched college ruled paper because I had a pack of it lying around. A rubber band works alright, but you might want to use a clip to secure the pages as you draw.