Think before you print
Read through a document before simply printing the whole thing out to handle later. Could you electronically file the information or copy-and-paste only the portions you need and then print out a single page rather than a dozen? With online media, look for the printer-friendly button so that the article uses as few pages as possible. And for documents that must look a certain way, always use the "print preview" button first. Also, print on both sides of the paper when possible.
Depending on the project, you could save reams of paper as well as expensive printer ink.