i been trying to quit but to no success and then one day i finally did it... cold turkey... juz like a snap of my fingers i stop smoking immediately... There is a catch or maybe a trick... i let you in on my little secret in quitting ciggies...
Buy yourself a bike, not just a bike but a damn expensive one. Give urself 1 week and spend the days leading to the last day of the week researching for a perfect bike from the dozens of brand out there. read lots of reviews online and you wont have the urge to smoke... then on the 7th day go down to LBS, do a bike fit and get that bike.
That is how i quit. my bike sleeps in the same room as me and i go to bed and wake up seeing him and he is the reminder of how i won the battle against nicotine. Oh by the way, there is really a difference in performance after quitting my smoking habit and im no kidding.