To print a large drawing on one regular size page, on the File menu, click Page Setup. On the Print Setup tab:
Choose a page size and the orientation that most closely matches the drawing page.
Select the Fit to 1 sheet(s) across by 1 sheet(s) down
To print a drawing on a large drawing page so it fits on one regular size printed page, you essentially tell Visio to shrink the drawing proportionally when it prints.
Before you fit the drawing to a single page, choose an orientation (Portrait—taller than wide, or Landscape—wider than tall) for the printed page that best matches the orientation of the enlarged drawing page.