First of all, I'd like to state that it's not recommended to diagnose yourself with panic attack. This should be done by your physician. With that being said, if you know that you suffer from panic attacks, it's also not reasonable to wait until the "attack" has passed. It's easier if you done something about it. Here are some panic attack treatment tips so you can be well-equipped when the time comes:

1. Gain understanding.
   First of all, you should understand what anxiety disorder or panic attack is all about. Raising your awareness level is vital because you can easily grasp the situation that you're in and take proper actions to dispell it. Keep this in mind: panic attacks can happen to anyone, whether they're stressed out, depressed or even happy. Sometimes it happen with no warning and seemingly no reason.
    
2. Know your triggers.
   Usually there are some triggers that develop into a panic attack. For example, if you feel really scared and anxious this can trigger an attack. Low serotonin and progesterone can also trigger an attack. The key is, knowing what triggers it so you can avoid it.
    
3. Be aware of panic attack symptoms.
   Some said it's justifiable not to know whether they're having a panic attack or not because they have difficulties in employing logic and perceiving situations when the time comes. This is indeed what happens commonly but it's not necessarily be the end game for you. Remember these signs by heart: heartbeat or palpitation, chest pain, hyperventilation or shortness of breath, stomach churning, upset stomach, trembling and shaking, muscle tension, sweating, dizziness and light-headedness, hot or cold flashes, tingling sensation or numbness, fear of dying, going crazy or losing control and feeling detached from the surroundings. When more than one happens, be alert.
    
4. Do breathing exercises.
   When the symptoms appear, one way to deal with it is by breathing deeply. This will enable you to shift your attention elsewhere. A good way to do this is do a mental count while breathing deeply. 3 slow counts in, 3 slow counts hold your breath, and 3 slow counts exhale. Do this over and over again until you feel the attack subsided. One effective way is also to breath into a paper bag because inhaling carbon dioxide that we exhaled can help correct your blood acid levels.
    
5. Keep a positive mind.
   "I'm aware I'm panicking right now. I'm certain that the attack will pass. I'm not crazy or going to die." By repeating this positive sentence you can make recovery come more swiftly. With most of the attack durations 5-10 minutes, it's necessary to keep this positive outlook. Some attacks can last more than half an hour, be sure that you're not going crazy.
    
6. Avoid being stressful.
   Although it's hard to avoid stressful situations, it's more beneficial to avoid unnecessary stress. If you know a certain someone stressed you out from time to time, or perhaps a certain situation, and anything else that cause unnecessary stress, avoid them.
    
7. Learn to say no.
   Most stressful situations can be resolved by just refusing it in the first time. Learning to refuse working overtime, for instance, can go a long way.

Coping with anxiety disorder or panic attacks can be hard if you don't have a good knowledge about them and the steps that you can take to treat them. It's better to learn more about it. You can visit libraries for references, do an extensive online research, etc. Or if you simply want a good ebook that covers panic attacks from A to Z, you can try looking into this link.