Order a Special Meal
Major airlines will have “special meal” offers that they give to those who book tickets in advance. These meals typically consist of edible food, unlike the stuff they usually serve. It’s not that expensive, and the extra carbs will come in handy in keeping you from going hungry during long flights.
Also, those who ordered special meals will get served first. That way, you’ll have plenty of time to rest afterward. While everyone else’s food finally arrives, you’ll already be two hours deep into your six-hour beauty sleep. Ask the airline to make sure whether or not they have special meal offers.