How to print invitations, or how to provide properly-printable pdfs of invitations?

Specifically this one: http://ift.tt/2f0unaW "save the date" is 2 inches skinnier than that actual invitation. We want our invitees to print out the invitations with as little hassle as possible.I'm failing to find examples in google of how to put these images on a page. I assume it's front and back, but the measurements don't jive with that. All I'm finding are more downloadable invites, and all sorts of really beautiful ideas and designs......but no how-to on layout and printing.Lend a guy a hand? via /r/wedding http://ift.tt/2hf7DEQ