One of my favorite grounding habits is mindfulness. I use a book called 30 Days to Reduce Anxiety by Harper Daniels for mindfulness strategies.

Something I've learnt (on my own, had a really poor therapist) is allowing space for processing a thought or emotion. Even if it's after the fact. Being compassionate to our thoughts and emotions is huge from my experience. One of my recurring anxious thoughts is "I'm scared to be hurt again." My compassionate and understanding process of that thought is "yes, you are scared to be hurt. It's okay to be. You've been hurt before, and that hurt is understandable. You are sfae in this moment." It always helps. And, afterwards, I feel better because my anxious thought and feeling was accepted and understood. It then was given direct evidence that it won't be like 99/100 times. It happens a lot less when I stopped trying to change it or fight with it. Just letting it be as is and giving it space to be there without judging it, but being compassionate towards it.