The trigger in an individual case could be something like a thought, a situation, or something as subtle as a slight change in heartbeat. Once the patient understands that the panic attack is separate and independent of the trigger, that trigger begins to lose some of its power to induce an attack. This is similar to the systematic desensitization used to cure phobias, but what it focuses on is exposure to he actual physical sensations that someone experiences during a panic attack. Others won't drink coffee or go to an overheated room because they're afraid that these might trigger the physical symptoms of a panic attack. Behavioral therapy is also used to deal with the situational avoidance associated with panic attacks.
Relaxation techniques can further help someone 'flow through' an attack.
These techniques include breathing retraining and positive visualization. Some experts have found that people with panic disorder tend to have slightly higher than average breathing rates, learning to slow this can help someone deal with a panic attack and can also prevent future attacks. In some cases, medications may also be needed. Finally, a support group with others who suffer from panic disorder can be very helpful to some people. It can't take the place of therapy, but it can be a useful adjunct.