Usually this will be dependent on the program you are printing from. For most MS Office applications, like Word and PowerPoint, on a PC you will want to check "Printer Properties" from the print screen (where you select the printer). Go to the "Finishing" tab and be sure that 2-sided printing is selected as the style.
On a Mac, use Command + P to call up the print menu. Where "Copies & Pages" is showing, select "Layout." Beside the "Two-Sided" option, be sure you have long-edge binding or short-edge binding selected depending on your preference.
On a Mac, hit "Command + P" to bring up printer options. Select "Layout" next to "Copies and Pages." Next to "Pages per Sheet" select the number of slides you want per page. When you choose to print ("File -> Print" or "CTRL + P") on a PC, one of the options usually defaults to "Full Page Slides." Select that option and choose the number of slides you want on one page.
Be sure you selected one of the Pharos printers to print to, rather than PDF or a different printer you might have available on your computer. Make sure you entered your EUID in the Pharos popup box. Your EUID is usually your initials plus four numbers. After entering your EUID, be sure you clicked “Print” rather than "Cancel" on the popup box. You also could have entered your EUID incorrectly.
The current version of Mac has had some issues with Pharos. We recently upgraded to a later version of Pharos which hopefully will resolve these issues. Restarting your Mac may be the best solution to this problem. Other problems that can prevent printing include the computer not being connected to the network.