Time Zones - Wake Up Call
To adjust to a new time zone, your morning routine is absolutely paramount. Sunlight is our body's key indicator that it's time to wakeup. Leave your hotel room curtains open so that the sun comes in in the morning - this will help your body clock adjust.
The other key indicator is breakfast. Food and coffee wake us up by kick-starting our metabolism, and if you eat breakfast at 7am at home, try to eat at 7am at your destination.
So, ideally, find a place in the sun and enjoy your usual breakfast, at your usual time.