Here are two stories of how mental model researchers print the diagram. Personally, I try everything I can to get someone else on the team to take care of printing. Printers (the machines) and I have had a lifelong turbulent relationship. So here's what real folks do:

Mary Piontkowski (using Omnigraffle): “I export to PDF, just the current canvas. Then I tell the printer the dimensions, usually based on the canvas size I have selected in Omnigraffle. I usually just have letter size (8.5 x 11” in the US) with portrait orientation selected, and it adds pages as I increase the canvas size. The width goes from 8.5 to 17 to 25.5, etcetera, as I add pages. Although I realized that I can bump it up a bit and still print on the plotter. I just count how many pages are shown in the visual "canvas size" interface, then that's what I tell the printer.”

Laura “Lad” Decker (using Visio): “I call the printer to confirm they can print on a color plotter, to find out the maximum size they can print, and to double check the price. (The mental model I printed for one client cost $500 for color. Black and white was a fraction of that.) Then, I make a PDF of the Visio file, and I send them the file via their website.

“I have been trying to compromise between what the plotter can print and what I need. The plotter is about 4' wide, which was how I choose the height of the model. I thought I could print a whole long sheet, but I discovered that I could only choose pre-set sizes of paper even though the plotter used a roll of continuous paper. So, I compromised and chose the ANSI Architectural size (ANSI E 34"x44") in the page setup menus. I had to shift my model sections a bit left and right to make certain the paper cut in a logical place. In the end, it was better that I had five large pieces of paper because I could update one section at a time and replace it on the wall more easily.”