Early in my sobriety, a wise man told me whenever I started to feel anxiety creeping in, to pay attention to the physical changes taking place in my body. If I was good with them, then keep on doing what I was doing. If I wasn't, breath deeply and slowly. On the inhale, think "help". On the exhale think this "too shall pass". As I was doing that, start to concentrate on areas of the body where I felt tension building and work on releasing the tension. When I felt calmed down and centered once again, finish with "thank you".
I think it worked for me for two reasons. The first was that I was never good with the physical changes going on so I always worked on lessening them by employing his suggestions. The second was because working on the first one took my mind off of my anxiety.