When a document is in a large font, consider changing the document's printing format to print several document pages per side of a sheet of paper.
In particular, when using a presentation application such as PowerPoint, you can print out several slides per page. Changing to a more compact printing format will not only allow you to save paper, but will enable you to see more of your presentation at a single glance. By distributing PowerPoint lectures as a PDF file with four or nine slides per page, faculty can encourage students and colleagues to either print in a paper-saving manner, or use PDF markup and management software to stay completely digital.
If you are viewing an word processing document that you can edit, you can also maximize the text you print per page by minimizing page margins, eliminating extra space between lines, and decreasing font size.