It seems that every long distance traveler you talk to has his or her own magic formula for avoiding jet lag. The truth, of course, is that there's no magic formula at all, just as there's no magic tablet or pill you can take either. Having said that, there are steps you can take before getting on an airplane and flying to another time zone that will go a long way to minimizing jet lag.
Firstly, it's important to maintain a consistent sleep pattern before departure. Your body is governed by its internal body clock, and one of the reasons you get jet lag is because long distance travel messes up your internal clock. If you maintain a good sleep pattern before leaving, your body clock will at least start the journey in good working order. Lots of late nights, staggered work shifts or not enough sleep will mean your body clock is already disrupted, and will magnify jet lag.
Also, think about what you're eating. A balanced and healthy diet helps you to get a good night's sleep, which helps stabilize your body clock. Aim for an appropriate balance of proteins, whole grains, fruits and vegetables, and avoid alcohol and caffeine wherever possible. If you typically have alcohol or caffeine on a regular basis, try to start eliminating it from your diet in the weeks prior to departure. It will help you to sleep better, and will also help your body adapt more quickly to a change in time zone.
Get some exercise! Maintaining a regular exercise routine is another important factor in helping you establish a good sleep cycle. If possible, allow twenty minutes a day for some aerobic activity, or at the very least go for a walk at lunchtime.
Now all the basics are in place, so that you have a good, consistent sleep cycle leading up to your departure, it's time to take some specific steps to overcome jet lag. Firstly, start to adjust your bedtime. Work out the time differences between home and your destination. If you're going somewhere that is six hours ahead, that means your normal bedtime of 10pm will actually be 4am at your destination. So for the last couple of weeks before your departure, start to bring back your bedtime a little each night, so that by the time you leave you're going to bed at a time much closer to that of your destination. It isn't always possible to get completely aligned - in the example above; you'd need to go to bed at 4pm, which isn't likely to make your boss happy! Still do your best, because the smaller the gap, the easier it will be to adjust.
Do your best to reduce stress before traveling. So make sure you've done everything you need to do well in advance, to avoid last minute running around and stress trying to get ready to leave. This is true of both work and home. If possible, arrange to have the last few days off work, so that you can have plenty of time to get ready without much stress. This also makes it easier to adjust your sleep cycle.
Traveling is great fun, and the last thing you want to do is waste time at your destination because you're suffering from jet lag. Spend some time getting prepared, and you'll find that you can minimize or even eliminate jet lag. Happy traveling!