There are some things you can do just as soon as you quit smoking, which will help make it easier for you to stay a nonsmoker. The first thing I tell all my clients is "Get rid of your paraphanalia." So throw out any cigarettes all all your lighters and ashtrays. When you see them later, they can be triggers. You don't need them anymore. You've chosen to be a nonsmoker.
If you have smoked in your car, it's time to make it the car of a nonsmoker. Wipe down all the surfaces in the interior of your car to get rid of the smell. A month from now, it would be like sitting in an ashtray if you haven't wiped it down. Keep a bottle of water with you and some hard candy (lollipops are great for this) in the console. This can satisfy that old oral craving habit and associations around driving.
Many commuters find they have very strong triggers around the commute itself. The client says something like, "I back out of my driveway and I light up my first cigarette. I get to a certain traffic light and I light up the second one. And about the time I pass McDonald's I light up my third so I have time to smoke it before I get to work." I suggest they change their commute. Drive on a different route if you can - avoid that traffic light and passing McDonalds.
In fact look at any trigger as an opportunity to change your routine to help you avoid that situation. If you always smoke after meals, leave the table as soon as you are finished eating. Replacing the old habit with a new habit like brushing your teeth, can be an easy method to let go of the old smoking habit. Buy two or three of those little portable toothbrushes that come in a plastic case. Keep one in your pocket or purse, one in your desk perhaps one in the console of your car. Get in the habit of brushing your teeth after meals. It will replace the old smoking habit and your dentist will love you!
It's a good idea to avoid places where people are smoking. You would not send a new AA member to a bar. In the same way, it may be just too uncomfortable to hang out on the loading dock with the smokers at break time. Take your break and take a walk, visit with the nonsmokers, lock yourself in a stall with a magazine. But you are choosing to be a nonsmoker, so why would you want to be a second-hand smoker?
Finally, focus on today. Don't worry about what you will be doing next week or a year from now. Your mantra can be "Today I'm a nonsmoker. Nonsmokers don't smoke. Not even one."