If your print support duplex printing then on the file menu click on print option. In printing dialog box click on Properties option. Here you will select a check box" Print on both sides" and Ok for print.
But if your printer does not support duplex printing then you can do it manually.
Print the odd number of pages first then on the back side of pages even number. From the printing dialog box select the option "Pages" and put the odd pages range separated by commas, for example 1,3,5,7,9,11. After printing on one side of the page, change the order of pages depending on the paper feeds in your printer.
For the back side enter the even numbers into the "Pages" for example 2,4,6,8,10 or choose "Even pages" from the print drop down box.