"Quitting smoking is easy, I've done it hundreds of times", once Mark Twain said.
If you decided to get rid of this harmful habit once and for all, the main thing you need for it is serious motivation. If you are about to say good bye to this habit just because it's fashionable nowadays, or following a neighbour's sample, you will hardly succeed in it… Remember how easily people, faced heart attack, quit smoking! Thus, when a person deals with such vital motives, he finds enough forces to change his habits. If you made up your mind to bear a healthy child or hold a sportive record, your chances are very big! However, there are no universal recipes - you should find the thing important personally for you. For instance, I quitted smoking when decided to go in for hiking. I got that won't go for a long distance with smoked lungs.
Note, that if your length of smoking is 10 years, alas, if you sharply refuse from cigarettes you may experience very unpleasant symptoms.