People often "forget" to breathe when the are stressed or upset; they hold their breaths or breathe shallowly, reducing their blood-oxygen level. This can increase feelings of anxiety and tension and make it more difficult to manage the situation effectively. Next time you're faced with a stressful or upsetting situation, check to make sure you're not "forgetting" to breathe.
Most people carry around more tension than they realize, which can lead to physical complaints such as headaches, muscle aches, and difficulty sleeping. The neck, shoulders, and jaw are common areas of the body to hold tension. A few times a day, mentally scan your body for tension (paying particular attention to those areas that carry tension most often), and try to intentionally let go of any extra tension you're holding. Notice the difference in how you feel once the tension is released.