Pick the Non-stop Route
If there are several possible itineraries for your destination, choose the one that brings you there in one stretch. It’s difficult enough to find sleep while several feet above sea level; it’s even more difficult to find sleep when you have a stopover. If a nonstop route isn’t available, choose the one with the longest uninterrupted stretch. If you do manage to find the ever-so-evasive sleep, it’ll be on that long continuous span of flight time.