Temporary insomnia, when you want to sleep, but you can't, can be caused by stress or excitement and usually lasts from several days to a few weeks. If it persists or becomes chronic you should consult a doctor.
Have a busy day
Researchers have found that people who have an active, busy day are more likely to have restful sleep at night.
Eat right at night
An amino acid in food named L-tryptophan can help you get to sleep faster.
When you eat a late-evening carbohydrate-rich snack such as rice cakes, dry cereal, air-popped popcorn, potatoes, corn, bagels, or a muffin, your body digests the carbohydrates, the pancreas releases insulin, decreasing the bloodstream concentration of all amino acids except tryptophan.
The now-strong tryptophan levels enter the brain where they manufacture a chemical called serotonin.
Serotonin is the body's sleep indicator and as your brain processes it stress and tension slide away.
Most people only need an ounce or so of carbohydrates to feel the effect within 20 or 30 minutes.
Try milk
Try milk to see if it works for you, however some milk is high in protein which can block the sleep-inducing effects of the carbohydrate content.
Count sheep
Any boring repetitive thought pattern will clear activity from your mind and help sleep.
Try a hot bath
Having a bedtime soak is an effective, relaxing technique.
A warm bath actually helps lower your body temperature, which is essential for triggering sleep.
The water's heat dilates the blood vessels, allowing heat to escape and rapid cooling immediately after.
Don't worry about time
Don't worry about what the time is or how many hours you've got left to sleep.
Once you've set your alarm, put it somewhere you can't see it.
Sleep on your back
Sleeping on your back allows your internal organs to rest properly.
If you must sleep on your side, try not to lie on your left - it causes your lungs, stomach and liver to press against your heart.
Avoid certain foods
Tyrosine-laden foods such as cheddar cheese, ripe avocados and fermented meats like pepperoni and salami.
Tyrosine agitates the brain and increases the number of messages it receives.
Caffeine is also a cause of wakefulness.
Stay in the dark
Your body associates light with sunrise - even if it's coming from a streetlight outside - so make sure your curtains are drawn and there aren't any lights on.
Distract your brain
If your brain is in overdrive and going over the day's events, get up and go to a room you don't associate with sleep and try and do a jigsaw puzzle.
Reading doesn't always work because if you're stressed, it can be difficult to become absorbed in a book and your mind may wander back to what was keeping you awake in the first place.
Something that keeps your eyes and hands busy, like a jigsaw, is best.
Put the kettle on
The ritual of making a cuppa can help to relax you.