1. Exercise. Even if you work out in the evenings. A new study had people do 30 minutes of high-intensity exercise a few hours before bed, and they were still able to fall asleep just fine.
2. Get some sunlight in the morning. It helps your internal clock adjust, so you'll get back to associating sunlight with waking hours, and darkness with sleep.
3. Get more magnesium. Either in pill-form, or from eating things like broccoli, spinach, kale, nuts and seeds. It has calming properties that help you to sleep.
4. Turn down the thermostat. There's no single temperature that's perfect for everyone. But studies have shown that most people sleep best somewhere between 60 and 68 degrees. That's the sweet spot for producing the sleep hormone, melatonin.