Jet lag planner
Daylight at the right time is the strongest signal for resetting your body clock. Choose your direction and the time difference to see a general plan.
Rough adjustment time: around 5 days. Sleep research suggests the body clock shifts by roughly an hour a day. Going east is usually harder, because the clock has to move earlier.
Daylight is most useful in: the morning, local time.
Try to avoid: bright light late in the evening.
Before you go: for a few days, move your bedtime and wake time by about an hour a day earlier, towards your destination time, if your routine allows.
When you arrive: eat and sleep at local times, keep naps short, and go easy on alcohol and late caffeine.
These are general patterns drawn from the NHS and sleep research, and people adjust at different speeds. This planner does not recommend taking melatonin or anything else. For the detail, read jet lag east versus west and how to adjust to a new time zone.