The following are based on a review of the research and the experiences of many people I have encountered over the years:
Get up at the same time every day. Wake up by the clock. That should be within one or two hours of the same time, workdays as well as on weekends.
Go to bed at night only when you think you can fall asleep. Wake by the clock, but go to bed when your body tells you to. People often find that if they fight their minds in this context, it can be a losing battle. If there’s a project you need to plan, and you cannot sleep, then just do the project. If you find yourself waking up earlier than usual, for a reason you can identify, then do something with that time. Rest assured your body will eventually want to make up the sleep later, and you might sleep all the way through the next night, or the night after.
Get as much light as you can during your desired waking hours. At least, this is the advice according to some experts. There is some evidence that more light elevates mood, although it’s not a fundamental or primary factor, except in more extreme cases, such as northern Alaska or long periods of no sun.
If you are having trouble sleeping, minimize naps during the day. People with insomnia often take naps, which sleep researchers advise against. It’s possible that 20 minute naps might be OK, while 2 hour naps create problems with sleeping later. Some people swear by their naps, although they don’t necessarily suffer from insomnia.
Minimize drugs that disturb sleep. Caffeine has to be minimized, at least for many. Minimize nicotine and alcohol, particularly in the hours before bedtime.
Exercise regularly. The best time is early morning to midday. Try not to exercise within five to six hours of bedtime.
It takes about an hour or so to unwind before going to sleep. So shut off the day an hour or two before bedtime. If you need to, write down your daily worries in a journal and close it. Then take a warm bath. Drink some warm milk with honey. Don’t be mentally agitated too close to bed — that’s the general idea here. Many people report that a reading ritual in the last hour or 90 minutes before sleep is good, so long as the reading is not ‘mentally agitating.’
Make your bedroom your sanctuary. This is where you get to enjoy eight hours a night of refreshing sleep. Some people sleep with soft or low music on, and report that this helps.