The best moment to quit smoking isn't New Year's but when you make the move to a new city. Tobacco addiction is linked to people, places, and everyday routines: that one friend you're always having a smoke with while shooting the shit, your kitchen that you come home to from work every day and the first thing you do is light up a cigarette as soon as that cup of coffee is ready. It's really hard to quit smoking when all of that stuff is still around.
I quit smoking a couple of years ago through what I call "the California therapy". I moved to California for 12 months a couple of years ago and planned to make another attempt - which I expected to be futile - at quitting smoking for good. I had been a smoker since I was 12, which made it about 14 years in total, and I had tried to quit a few times already. However, since all of my habits changed drastically from one day to another, quitting was rather easy this time. It also helped that, compared to Germany, smokers are nowhere to be seen in California. Smoking is banned in all bars, tobacco is expensive, and even the campus at UC Davis was smoke-free (which is unheard of in Germany: in order to get into the humanities building at my old school you'd have to pass through a cloud of smoke). When I came back to Germany, the thought of smoking felt repulsive. I've lived a smoke-free life for the past 5 years now. The last cigarette I had was in one of these shitty smoking booths at Frankfurt airport, looking out at the plane that would take me to California.
So, if you're planning to quit smoking AND planning to make a move, try to combine both. It's all about the right timing.