Open the document you want to save as a PDF.
Choose File > Print or Command + P.
Click the PDF pop-up menu at the bottom, then choose Save as PDF.
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Going to save gives you a few options, specify a location other than Documents if desired, and you can fill out author information, the title of the PDF document, subject, keywords for searching within the document, and even specify a password and editing options by choosing “Security Options” if you want to protect the file from others having unauthorized access to it.
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Go to that folder (default is Documents) to find your PDF file.