Panasonic KX-P7305 - Manual (Page 102)

Setting the Printer Driver (Mac OS 8.5 - Mac OS 9.2)
Macintosh Macintosh Windows Basics 97
11
Click Printer Specific Options menu and select Layout menu.
12
Click on the Print on Both Sides check box and click your desired
binding style icon.
13
Click [Print].
The document will be automatically printed on both sides of paper.