There are generally two approaches.
One is to give it up on the spot.
The other is a cessation program. Gradually cut down over a 4 or 5 week period and finally be free. How many do you smoke day. 20? 25? 50? Your pattern determines the program best suited to you. With hypnosis you get the support and motivation to change, so that by the end of the program you've made significant lifestyle changes.
It's also about setting the goal of what day will you quit. So that on the day in question you will be able to say "I DID IT"!