I practice mindfulness meditation. And part of my focus is on my breathing, which obviously if you are "watching" your breath, you aren't going to be holding it. my T also trained me to breath from my belly, which has effects on the parasympathetic nervous system, eventually helping to relax your whole body. He also taught me to use a meditation app that rings bells randomly throughout the day and to take a "belly breath" whenever it goes off. To randomly remind you throughout the day to bring yourself to the present and to your body. If you have a smart phone and want to try this, there is a free app called lotus bud that has bells that ring at random intervals.