This breathing exercise “switches on the parasympathetic nervous system*, which is our rest and digest mode. It can help you all asleep and also remove anxiety.
Lie down or get in comfortable position.
Breathe in and out through the nose for a few cycles to settle in.
Next, bring your attention to your exhale for three rounds of breath.
Begin to extend your exhale by 2-3 counts.
Repeat extending your exhale for five minutes.
As you practice extending your exhale you might naturally increase the length by more than 2-3 counts. That is a sign that your nervous system is regulating.” (source)
Here’s an audio file of the directions:
* The parasympathetic nervous system is one of three divisions of the autonomic nervous system. Sometimes called the rest and digest system, the parasympathetic system conserves energy as it slows the heart rate, increases intestinal and gland activity, and relaxes sphincter muscles in the gastrointestinal tract. (source)