I usually offer PDFs at 8×10 (U.S. standard frame size) or 8.5×11 (U.S. letter size). Let’s assume we’re starting with a PDF in one of those sizes, and let’s assume you aren’t using Photoshop (highly recommended!) or a comparable file-handling app. Printing the PDF from default programs (Reader, Preview, Word) should give you a dialogue box that allows you to adjust sizing by percentage.
Make sure you save your Word, jpg or Excel files as a pdf. Pdf’s are generally easier to print. They can also be secured so that no one can download and change your product. Most programs give you the ability to “save as” to a pdf. If you use an Adobe product like Illustrator, it’s part of the program. If you use other art/graphic sites like Canva, Picmonkey you can always convert or print the jpgs to a pdf.