Preventing a relapse
Unfortunately there is no clear evidence that supports any method of staying smoke free once you have quit. People can continue to use NRT products to reduce the urge to smoke and when they are ready they will quit.
The best defence is the knowledge that smoking cessation is a journey and not a single event. Nicotine receptors in the brain can be switched off during the quitting process, but as little as a few puffs of a cigarette, months or years later will switch them back on. When this occurs most people will find themselves addicted smokers again.
Stay away from that one cigarette!