What's the best way to recover from a particularly bad panic attack?

To use some grounding techniques. When having a panick attacks, your senses are altered. You are disconnected from reality and this why you need to focus on what you see, smell, touch, hear and maybe even taste to come back to a more calmer state. Deep breathing exercises can help too (expecially in case of hyperventilation). For more info : http://www.healthyplace.com/blogs/treatinganxiety/2010/09/top-21-anxiety-grounding-techniques/

Some water and a nap can usually help to restore the body after a bad panic attack. Trying to keep yourself occupied afterwards can also be useful because that distracts from any lingering bad feelings.

Take time to be gentle with yourself. If you need to be alone, be alone. If you need to be with someone, talk to someone you trust and say "I just need to sit with you for a little while, I just had a horrible panic attack, is that okay?", read a comforting book, listen to your favourite music. I have an "Anxiety-Free" playlist of music that just makes me smile.

Self care a whole lot as soon as you can. Make your favorite food or drink, curl up in a blanket, take a warm bubble bath, put on lotion, etc.

Remove yourself from the stressful situation (if possible) focus on your breathing and ask your self if your fears are valid.

Try &take a deep breath in ,close your eyes &dont think about anything&just breath out slowly do it a few times..take a few sips of water, wash your face with some cold water..and try doing the breatheing excesise again..put on some soothing,calming music if you are able to

Take a hot or maybe even cold shower. Put ice cube on wrist. Walk. Watch a funny movie. Play a game.

Focus on your breath. Focus on the time you take for each breath and count each inhale and exhale.

I breathe with my diaphragm and sometimes I journal about what I was feeling. I also use my healing stones by holding them and thinking positive thoughts.

Lay down in bed if you're at home. Get some ice water and sip it. Close your eyes and take deep breaths until you feel normal again.