Breathing is done without much thought. However, improper breathing can upset the oxygen and carbon dioxide exchange and contribute to fatigue and other physical and emotional disturbances.
According to The American Institute of Stress, 20 to 30 minutes of "belly breathing", also known as abdominal breathing, each day can reduce stress and anxiety.
Find a comfortable, quiet place to sit or lie down.
1. Place on hand on your upper chest and the other hand on your belly, below the ribcage
2. Allow your belly to relax, without forcing it inward by squeezing or clenching your muscles
3. Breathe in slowly through your nose. The air should move into your nose and downward so that you feel your stomach rise with your other hand and fall inward, toward your spine.
4. Exhale slowly through slightly pursed lips. Take note of the hand on your chest, which should remain relatively still.
Start out by doing the exercise three times and working up to 5 to 10 minutes, one to 4 times a day.
Source: Verywellmind.com