Before you go on a trip, try and shift your clock a bit when you are still home. When flying from to the west, get up slightly later every day. When flying to the east, get up slightly earlier.
If possible, book flights that will minimize your jet lag by following the simple adage: ‘Fly east, fly early. Fly west, fly late.
If you need to sleep during the trip, try to avoid sitting on the sunny side of the plane. For flights in the northern hemisphere, the sun will tend to be on the left side of the plane when you fly west, and on the right side when you go east.
As soon as you board the plane, adjust your watch to show the time at your destination, and try to fit into this new time schedule as soon as possible. If it is time to sleep, try and close your eyes for a while. If it is dinner time, eat something (even a light snack is okay).
Some people believe that melatonin supplements can help control your sleeping patterns and thus help you adjust to new time zones. Research suggests that daily doses of melatonin can help alleviate jet lag, and short-term usage seems to have few negative side effects. Consult your doctor before taking any medication.
When you arrive at your destination, adjust your circadian rhythm by using the following simple rules of thumb:
If you really cannot keep your eyes open during the day, take a quick nap, but set your alarm to make sure that it is no longer than two hours.
Source: Night School by Richard Wiseman