Adobe InDesign has a facility for printing out in ‘booklet format’ so with the duplex A3 laser printer you can produce a collection of pages that just need to be folded in half and bound – page order and spreads across pages are all handled automatically. This process seems a little complex at first but it does simplify what can be a frustrating experience.
Instructions on how to do this on the A3 duplex printer are available as a PDF download