Tips to stop body armoring?

I hold a ton of tension in my body, especially in my shoulders, neck and jaw. I have poor posture and I need to use a mouth guard because I grind my teeth when I sleep

I try my best to be mindful and when I catch myself body armoring I take a min to take a deep breath to release it, but no matter how much I do this, my default setting = tension. Does anyone have any tips? Thanks