Start living on the timezone you are traveling to as soon as possible. Get on the plane & change your clock & start setting your sleep patter with the destination time zone (helps if you have sleeping pills!). I always find that drinking lots of water also helps. Try & keep your first few days light so that if you are suffering badly you give yourself time to adjust.
I think Leftylk has it right, but I'd add that you should avoid using too much caffeine/alcohol to get yourself on schedule. Additionally I find that not comparing time back to my time zone of origin helps. Don't say "but it's only 8pm in San Francisco" if it's 11pm and you're in New York.