Save Your Documents as PDF Files

You probably know this already, but it’s worth repeating, just in case. Use File > Export > Create PDF/XPS Document, and keep clicking until you’ve saved your file as a PDF. (On a Mac, choose File > Save As, and select PDF as the output format.) Take the trouble to click the Options button when you save the file. You can use that button to save some, but not all, pages to PDF and to choose other advanced options.