HP LaserJet 9000 Printer series - Manual (Page 15)

ENWW Making booklets 15
2 Follow the instructions for your driver type:
• If you are using a PCL driver, click the Finishing tab. On the
Document Options menu, select Print on Both Sides. On
the Booklet Printing drop-down menu, select a size from the
list.
• If you are using a PostScript® (PS) driver, see the program
Help files for information on activating booklet printing.