Sunlight & Melatonin. Your internal clock is set and reset daily by sunlight and melatonin (your body's sleep hormone). Get out into the morning and evening sunlight and take melatonin before bedtime. Melatonin is available over the counter. Additionally, you will want to eat at the appropriate times on your new schedule. You will be adjusted in a few days.
Conform to light. It is challenging to get your internal clock to readjust to a new time zone. Try to get up with the sunrise and get plenty of light early in the day. At night try to reduce your light exposure. A medication called rozerem (ramelteon) can help reset your clock more quickly. On average it takes one day to adjust to each time zone different from your home - thus 3 time zones takes 3 days to adjust.