During the week before your "quit day," do these things:
Pick a good quit day. Don’t choose a day that’s in the middle of your most intense month at work, or right before finals, or while a loved one is seriously ill.
List all the reasons you want to kick the habit. Save them on your phone. Print them out on index cards and stash them where you used to put your cigarettes -- in your purse, in your desk drawer, in your nightstand.
Pay attention to when you smoke, where, and with whom. Then make plans for what you can do instead. Think of alternatives that will keep your mind and body occupied.