Jet Lag can be certainly tough especially with those long-haul flights. There are 3 main things you can do to help fight Jet Lag.
1) Drink plenty of water before, during, and after your flight.
2) Fly by day, and arrive by night. This will allow more time for rest. If you can... get out in the sunshine as soon as possible to soak up some rays.
3) Get some exercise as soon as possible to get the body moving again.
When crossing only a few times zones it much easier on the body going westward. This frees up more hours in the day, and allows the body extra time to recuperate.
Happy and Safe Travels!