1) JET LAG.
If you're going to be on a 16 or 17 hour-long flight, you're probably changing by several time zones. Florida is exactly 12 hours' difference from China, and that is my number one long-haul flight, personally.
If you want to have the best trip possible, this will take discipline, be 100% accountable to yourself on this. Set alarms and live by them. If you set an alarm to wake up, wake up when it goes off. If you need help sleeping, bring appropriate help (medicine, eye mask, neck pillow, ear plugs, etc. More on that later).
So...when should you get up? Big question. I'll use the "Florida to China" example to show you how I calculate.
"Normal for me" = wake up about 6:00 to 8:00 am every morning, then bed by about 11:00 pm. This is at most 17 hours awake on any given day. I typically arrive in China around 2:00 or 3:00 pm. So when do I need to sleep? When do I need to wake up? I need to wake up "about 17 hours before 11:00 pm in China". Or "I need to wake up at 6:00 am (my normal wakeup time) in China... For a typical 16 hour flight arriving at 3:00 pm in China, I will set an 8 hour alarm on my phone so that I sleep for 8 hours, then wake up and stay awake for the last 8 hours of the flight. From 3:00 pm to 11:00 pm is another 8 hours, so I will be up for a total of 16 hours before my scheduled sleep time.
The other thing to remember is not to let yourself go to sleep too early. I have a hard and fast "9:00 pm rule," no napping and no sleeping before 9:00 pm local time. If you go to sleep too early, you will find yourself waking up at 3 in the morning, unable to get back to sleep, which will just make you super tired on the following afternoon, thus perpetuating the cycle of jetlag. Once I settle in, I try to get in a habit of showering at the end of the day, then walking somewhere to eat dinner, then taking a long walk around the neighborhood or a shopping area, and trying to stay out of the hotel room until about 8:30 or so. I find that if I sit around in the hotel room in the afternoon, I will fall asleep way too early.
2) How to sleep on the plane. There will be small airline blankets in the overhead bins. Be sure to snag one of those on the way to your seat. In your carryon bag, you want to have earplugs, a GOOD travel pillow, a sleeping mask, and headphones. Also, if you have difficulty sleeping, you may want to have an over the counter or prescription sleep aid, just know your body, seek medical advice if you need to, and make sure you're not going to take something that's too strong, or you might wind up oversleeping on the plane.
Earplugs are great to have, whether it's to help you get some good sleep, to block the roar of the jet engines, or to keep you from having to listen to somebody else's baby scream for 10 hours straight.
A good travel pillow will be worth its weight in gold, but a bad one will only become a burden. I got the "Trtl Pillow" on a good sale, and I have been extremely happy with it. It wraps up to a very small, lightweight package which stows easily, and when you use it to sleep, it wraps around your neck, keeping you warm and cozy and propping your head up comfortably. You can even cover the lower portion of your face with the neck wrap part of it, which keeps you from breathing unfiltered cabin air and keeps your nose and mouth naturally humidified by the moisture in your breath.
Sleeping masks are typically inexpensive. Shop around and find a comfortable one, especially in case the person seated next to you wants to use the reading light for the duration of the flight.
For headphones, I prefer the larger option, "on-ear headphones," or "over-the-ear headphones". They take up a lot more room in your carryon bag than a set of earbuds would, but I prefer larger headphones for a few reasons. First, because it's always obvious that you are wearing them, so the people seated around you will typically avoid bothering you, because they will think you are listening to music or to a movie. Secondly, even if you don't go to the expense of buying noise-cancelling headphones, the large ear cups will still block out a lot of the ambient sound around you. Lastly, the sound quality is often better, and I don't like the way earbuds kind of "shoot sound right into my head," I like sound that has at least a bit of room to expand and mature before it tries to make its way into my ear holes.
3) How to stay awake on the plane. Back to your waking time on the long flight... when your wake up alarm goes off, wake up, go to the restroom, wash your face, brush your teeth, and take a walk around. Long-haul planes are typically very large, so there will be room to walk. There will be a galley in the rear and another toward the middle of the plane, before you get to to the first class cabin, and I like to walk from one to the other a few times, pausing at each one. Snacks like chips and pretzels will be openly available, so do avail yourself of them. Water and other refreshments will be there for the taking, so make sure you keep yourself very hydrated. Dehydration will sap your energy and leave you open to illness. I've also learned that if you ask very nicely, a flight attendant is always willing to make you a fresh pot of coffee, usually because they could use a cup as well.
Eat, drink, walk a bit, and avoid illness and blood clots. A toothbrush and some toothpaste are excellent travel companions, and keeping your breath fresh will help you to feel not only cleaner and refreshed, but also more awake.
Make use of in-flight entertainment, there are typically movies and music on-demand. You can write in a journal or read a book, but whatever you do, keep your mind entertained and you will have an easier time staying awake. Be prepared to be out of sync with the rest of the passengers, as most people will sleep for the duration of the flight. Don't worry about it, you're doing the right thing, and they will have much worse jet lag than you in the coming days and nights.
All of the above tips require a bit of preparation, but you will find the reward is well worth the effort. If you use the above method, you will typically be able to completely adjust to your new time zone within 2 days, 3 days at most.
Bon voyage!
