An additional time-saving technique that I use is to pause the printer, run several jobs, then go put the appropriate paper tray in place before resuming the jobs. Not having to go back and forth between my computer and printer saves me about 70 stair steps. Here’s how it works:
Before printing, open System Preferences > Printer & Scanners, then double-click the printer in the Printers list. In the window that appears, click the Pause button. Important: Do not close the window where the Pause button appears.
Next, print the file as you normally would. When the warning message about the printer being paused appears, click “Add to Printer.” Repeat for each document that you want to add to the printer’s queue.
To take this even further, I created a Keyboard Maestro macro, triggered via Alfred Remote, to unpause the queue when I’m on the other floor. You’d need both of these pieces of software — which I recommend — to do this, so I won’t dwell on the details. But, briefly, you need to trigger the macro via Keyboard Maestro’s web server. The macro source is available at this gist.