I've heard of people who were quitting smoking that found it helpful to put their empty fingers up to their lips, and inhale as if they were smoking, several times over a period of how ever many minutes a smoke would normally last. Something like the breathing pattern tricks some part of you and calms you down like a smoke did. I don't personally know anyone who did this to quit smoking, the only person I know who was able to quit just decided one day that he is not smoker, and that was it, so I can't vouch for it, but it doesn't seem like it can do any harm, so give it a whirl and let us know if it is helpful at all.