To mellow the effects of jet lag, try to arrive a couple of days early to give your body enough time to adjust. It may help to set your watch to the new time before you leave and to act accordingly. If at all feasible, this could involve slowly adjusting your sleeping and waking hours to the new time zone. This may seem trivial to you, but a well-slept and alert traveler is much better equipped to deal with cultural differences than someone who is underslept and exhausted.