Exercise. There are too many benefits to exercise to list them all here. When it comes to sleep, exercise will make it easier for your brain and body to power down at night. Furthermore, obesity can wreak havoc on your sleep patterns. The role of exercise only becomes more important with age. Fit middle-aged adults sleep significantly better than their overweight peers. One caveat: avoid exercising two to three hours before bedtime as the mental and physical stimulation can leave your nervous system feeling wired and make it difficult to calm down at night.
Temperature. Most people sleep best in a cool room. The ideal range is usually between 65 to 70 degrees Fahrenheit (18 to 21 degrees Celsius).
Sound. A quiet space is key for good sleep. If peace and quiet is hard to come by, try controlling the bedroom noise by creating “white noise” with a fan. Or, use ear plugs (here's a good pair).
Alcohol. This one is a slippery slope. It is true that having a drink before bed — a “night cap” — often does help people fall asleep. However, while it makes it easier to fall asleep, it actually reduces the quality of your sleep and delays the REM cycle. So you fall asleep faster, but it's possible that you'll wake up without feeling rested. It's probably best to improve your sleep through other methods before resorting to alcohol to do the job.