Here are some suggestions. Before the flight get plenty of rest and exercise. It seems that when a person is healthier they find it easier to cope after landing.
You might try adapting to the destination time in advance for upto a month in advance.
During the flight, make sure that you drink enough water to avoid dehydration, as the cabin air is typically very dry. And (despite what they offer you on the plane) caffeine and alcohol are probably the worst things to drink!
Also traveling west-to-east is generally mroe difficult to east-to-west. This is because most people have a body clock that is slightly more than 24 hours, so it is better for them to cope with staying up a bit longer, than it is to sleeping a bit earlier.