Drink water every hour. At 0 percent to 2 percent humidity, cabin air is drier than any desert. Avoid alcohol and coffee because they have a diuretic effect. Also, drink plenty of pure water for several days after landing. High-carbohydrate snacks from home are a better choice.
Airline meals are typically high in fat and preservatives, while low in carbohydrates.
If it lands in the morning, get as much sleep as possible on board. Bring sterile cotton for your ears, an eye mask stating 'Do not disturb,' an inflatable neck pillow, and a sweater or shawl and socks. If the air remains stuffy, ask for an oxygen bottle. Upon arrival, don't rush to a stuffy hotel. Get some fresh air and exercise.