How do you avoid jet lag?

The only way is not to travel. Because your body clock is used to going to sleep and waking up at certain times. When you fly to different time zones your body is still used to the time at home, not the country you are in. Your body is telling you, you should be asleep now, when it could be the middle of the day...

Counteracting jet lag
change your watch as soon as you get on the flight: the quicker you adapt to the time zone the lower level of jet lag is likely to be
when you arrive in the new time zone, spend some time outside during daylight hours as natural light can help align your body clock
try to adjust your bedtime and mealtimes to the local timetable as soon as possible
schedule commitments at times when you are likely to have maximum energy: in the evenings after flying east, or in the mornings after flying west
the impact of alcohol on the body can be two to three times more potent when you're flying, so one glass of wine during the flight has the effect of two to three glasses on the ground. Avoid feeling even worse with a hangover by reducing alcohol intake before and during your flight
get as much exercise as you can: walking up and down the aisle, rotating your ankles and doing gentle stretching exercises in your seat can help to reduce discomfort and allow you to have a more relaxed flight
during extended stopovers on a long-haul flight, try to grab a shower: it can wake up your circulation and get things moving

dont go on a jet!!

taking a flight that goes 'overnight' helps because it simulates a normal night and doesnt force you to be on a plane while it is completely light out side. also, try and sleep on the plane. the best thing i have found is that if you arrive at your destination early in the way, STAY AWAKE! dont run to your hotel and go right to sleep. stay awake even though you may be exhausted, and you will find that you get acclimating to the new time zone.

also, try going to your doctor and asking for some ambien or lunesta for a few days so that when you get there, you can take the ambien at your normal bed time, and use it for a few days to get used to the new time zone.

Go by boat

i travel all the time and i find the best way on your way to the airport start preparing to act like you are in the time zone you are going to, big meals etc hold out until its dinner time where you are going and try and sleep (usually with the aid of a Glass of wine or twenty) the same as where you are going.
Does not always work but 9 times out of ten it does.

I travel all the time and I agree with the above.

the only way to counteract it is to get on the new time zone early and eat/sleap according to the zone you are going to.

If your going east to west is the easiest. I find its best to stay up and just have a very long day.

West to east I usually have a nap as soon as I am settled where I am going then get on track with the new time zones.

You could try changing your eating and sleeping habits slowly during the week before you travel, but for me thats a waste of time.

err dont travel?

dont fly