Okay, so for full knowledge before you read this simple explanation you can read my very long-winded and detailed explanation of trauma and anxiety here on my blog. It will give you a more thorough understanding of why the technique below works. Very briefly, the brain has a fear center with a part called the amygdala. The amygdala does nothing but look for reasons to be afraid and sound an alarm. If we experience adversity or trauma as we grow up, it becomes hyper-sensitive and gets triggered too easily by things in our environment. When this happens, the brain sends a signal to the body to go into fight or flight mode. It does this by triggering the nervous system to shift, which triggers the many familiar symptoms of anxiety or panic; racing heart, quick and shallow breath, muscle tension, sweating, confusion, etc.. These are useful when your life is in danger, but not when you are worried about everyday life stressors. So to help your brain understand, you regulate your body instead. If you do this often enough for long enough you start to become good at it, and your body begins to learn to regulate again on its own. So do this technique any time you remember, set an alarm for every 15 minutes, do it before and after a normally stressful event, any excuse. The more you practice the better you get, faster. So anytime you feel nervous or anxious do this to regulate your nervous system. Also, do it before events you know are stressful and right after, to teach your body. Lastly, do it any time multiple times per day.
All you have to do is 2 things that take 60 seconds. You will do 4x4 Breathing and then you will do a body relaxation exercise called "noodle". 4x4 Breathing: This is very simple, just count to four in your head while you breathe in, count to four as you hold your breath, then four as you breathe out. Do this four times, hence 4x4. You do this to slow down, control, and deepen your breathing. To do it right you have to breathe deep, using your diaphragm. This is a muscle that helps to control breathing, but we breathe shallow into our chest, especially when anxious. There is a trick to make yourself breathe deep with your diaphragm. Interlace your fingers and put your hands behind your head, then pull your elbows back like you're spreading wings. You will notice your stomach will now expand as you breathe deep, this is the correct way. Slow down and control your breathing, calm, you are safe.
"Noodle": This is a technique to relax the tension being built in your muscles. This tension is because your body is preparing your muscles for explosive energy to fight or flight. You simply sit or lay down and let your entire body relax, collapse, melt. Let any tension out, don't put any effort into holding up any limbs. Then to finish it off you want to do a quick body scan. Take your attention to your forehead. Make sure it is relaxed and not furled - your eyes should be closed but not squinted, your cheeks relaxed, your jaw relaxed and mouth slightly open, tongue resting and not pressed to roof of mouth, shoulders dropped away from the ears. Let all the tension slide down all the way down to your feet.
By doing these you regulate your breathing and your muscles, regulating your nervous system. This then sends a signal back to your brain telling it the situation is safe. Through the body the mind is quieted.