When you can’t sleep, concentrate on extending your exhales. Inhale for a count of four, and exhale for a count of eight. In yoga (I’m a yoga teacher), exhales are associated with release and detoxification. By taking such long exhales, you help yourself relax and it makes it much easier to let go of all the thoughts that are swirling around in your head, keeping you up. If that count it too long for you, try inhaling for three and exhaling for six. I use this technique when I wake up in the middle of the night, and it only takes a few rounds before I am drifting back off.