My laser printer, a Samsung CLX-3175, does not have any tool for automatic duplex printing. Achieving such result manually is not difficult, but may take some trial and error in order to get the settings right. That’s exactly what I’ve done, and I’m writing this post as a note to myself. Should it be useful to anybody else, however, by all means let me know with a comment.
Keep in mind that this is for my own printer, and that I use OS X 10.6 “Snow Leopard.” Results may vary with different printers and/or operating systems, so make your own tests. If your printer outputs pages “face down,” this will probably work as it is. Most ink-jet printers on the other hand output prints “face up,” so some adjustments will be necessary.
In any case the steps for my own printer are very, very easy (once you’ve figured them out correctly):
- Print all odd pages in normal order
- If the total number of pages is an odd number, take the last sheet and put it away for the time being
- Take the (remaining) sheets and put them back into the tray after rotating them 180°. Do not flip them in any way!
- Print all even pages in reverse order
- If you put the last sheet away in step 2, put it back at the end of the stack
- There is no step 6
Enjoy. 
