A technique that I was taught by my psychologist that I find works fairly well (better with minor attacks or the early onset of an attack) is called the grounding technique. Because I am a person who seems to always be anxious about what is going to happen in the future she recommended this technique. What you do is as soon as you feel an anxiety attack coming on or if you start worrying about something that might happen in the future sit down in a chair, or whatever you can sit on, and make sure your hands can touch whatever you are sitting on. Start looking around and out loud, if you are in a place you feel comfortable saying things out loud, start listing the colors of things around you. i.e. if you are sitting in a blue chair say "blue chair" out loud, if there is a green blanket say "green blanket" out loud. List everything out loud as fast as you can and as many times as you want until you don't feel the anxiety coming on anymore. What she said that this exercise does is bring's you back into the now and the moment rather than freaking out about something that could happen to you or someone else in the future. Whether you are anxious about something happening in 30 seconds or 30 years it helps to focus on what is the present. If you are in a public place or a place you don't feel comfortable saying things out loud then just list the things in your head but make sure you stay focused on listing things and try not to get distracted. Anyway just thought I would make this suggestion because I find it does work a lot!!