For specific steps on how to print from each browser, please see this article: http://support.gliffy.com/entries/96901917-Printing-from-Different-Browsers-in-Gliffy or our User Manual: https://www.gliffy.com/user-manual/?productId=3#article_417
To Print your diagram from Gliffy, go to File->Print.
Some browsers have different behaviors when printing.
Chrome Browser: In Chrome, you will need to set your margins to "None" in the print system dialog that comes up after you click "Next".
For all browsers you will need to also make sure you have your Paper Size and Page Orientation set correctly in the print dialog screen that comes up after you click "Next".