Printing on both sides of the paper isn’t that huge a deal, but it does depend a bit on the software and on the printer. Adobe (pdf’s) has the option to print on both sides of the paper. Both of my printers do in their printing preferences too. Basically it will print all the odd pages, then tell you to put the paper back in, and it prints the even pages. Most of the printer drivers tell you right on the screen.
The thing that makes it a pain is if you put the paper back in wrong – so that it is printing on the same side again – or so that the pages are upside down…. trying to fix that without wasting ALL the printing you already did can be pretty tricky….