can't figure out how to maneuver

Hey, all- just loaded the game from Steam, and I can't figure out how to do orbital maneuvers.  As in, I cannot figure out the UI controls to use on the computer to do orbital maneuvers.  The videos I checked have a button on the screen that makes the three-axis balls appear, but I don't have such a button on my Mac.  WTF?  Is it now hotkeys?  (I've tried every key on the keyboard.)

Is there a manual somewhere?  Or even just a list of hotkeys?  (I've been googling without success.)