Good for you! I'm not a smoker, so I can only tell you what I've heard about quitting. Do whatever it takes for you. Some people plan it out, some people stop cold turkey. I say: just quit. Launch a full on attack and be strategic. Know that you might feel rough for a few days, so plan for it. Exercise more those days, have gum on hand, listen to great music...whatever it takes. You'll be cranky: deal with it. You'll want to start again: don't. You'll be tempted when you drink: expect that and plan for it by having mints, straws and whatever else you can put in your mouth besides cigarettes.
I also believe this is a great time to start doing something that makes you feel incredible. If you like writing, write more. If you like running, run more. If you like dancing, dance more. You get the picture. Just do it. You only have better health, better skin, better breath, better breathing, more money, and more energy to gain. Now go get 'em, tiger! (smacks ass).