How to print double sided on Mac?

Question

The enable icon is shadowed and I can't click it to enable it.  using a HP Deskjet printer connected to USB

Answer 1

This is the method I use for printing a 9-page manual. I have a printer that provides Face-down delivery of the finished pages.
1) First, print the even pages oddly (in reverse order)
2) -- then flip the output stack to the input tray, ready to print the reverse sides --
3) Then print the odd pages evenly
so after step 1, I have pages 8,6,4,2 face down in the output tray. I take that stack and move it to the input tray facing the right way to print the odd pages. Then pages 1,3,5,7,  are printed on the opposites side of the paper, and page 9 prints on a blank sheet. Pages are in the output tray in correct order, face down.
The controls for doing this are on the "Paper Handling" pane of the standard Print dialog box, under Pages to Print {all, odd, even} and Page Order {Normal, Reverse}.
If your printer provides face up delivery, you will have to draw yourself some little diagrams and figure out exactly where to change my procedure, or invent a comparable one for your situation. The advantage to the rhyme is that I don't have to try to find the stinkin' piece of paper with the little diagrams a year from now when I want to print two-sided again.