The secret for me was not to "give up smoking" because then you are psychologically giving something away for nothing in return - your subconscious mind does not like that. So don't try to give up smoking. Just stop smoking temporarily.
So each time the urge came up to smoke I said I would defer the decision for a few minutes and make the decision about having a cigarette a little bit later. So I never stopped forever I just "stopped for a short while". So far the decision to have a cigarette has been deferred for about 15 years.
I also made the decision to smoke a tangible choice between all the good things I would get from not smoking, and the things I would get from smoking. "I choose to be healthy and have clear lungs and not die young, instead of choosing to have this cigarette". As opposed to "I'm going to deprive myself of a cigarette that I really want, for nothing good in return."