The sniff technique helps me. Its when you take three big sniffs in then breath out three times with either an f, s or sh sound

Taking in a really short breath of air and immediately gently exhaling through your mouth making a "TSS" sound. Then, continue exhaling for as long as you can (not forcefully though!) and start again. If you grin or show your teeth when getting started with this exercise, you'll be more focused on your breath patterns! Of all the techniques I was given in therapy, this one worked the best! It might take a while to get used to going right into the breathing techniques during or after an attack, but if you practice when you are feeling well, you will eventually have this become your safe and healthy response to the attack!