But the night before you travel, stay up all night and then crash like a ton of bricks on the flight. This works better for night owls that morning doves.
No alcohol or coffee in the 24 hours before the flight or on the flight.
This depends on what direction you're travelling in but when you arrive and it's still daylight, try to take a 20 or 30 minute walk during twilight. Dusk may trick your brain into thinking about getting to sleep soon. Light exercise such as walking or stretching or some sun salutations will help in any direction.
When I used to travel a lot, I found that the older I became, the longer it took me to get over jet lag. After 40, I was taking about 10 days to get right after a trans-oceanic flight. At least I got a lot of reading done around 3 a.m.