As someone who recently quit smoking, and is 100% sure he will never have another cigarette, I must say that quitting smoking really isn't that complicated, once you realize how unimportant your petty desires for a cigarette actually are.
I just plain woke up and quit smoking. It wasn't even that difficult. I just woke up, and the first thought on my mind was "I should quit smoking", and that day was the first day in five years I didn't have a cigarette. How did I do it?
It's really fucking simple, people: Don't smoke. When you want a cigarette, just realize that your body is being defective, lying to you, and that you don't actually want one, and that a part of you will hate yourself, deservedly so, for your inability to practice basic restraint and sacrifice for your own greater good. Realize that you have a higher, more evolved layer of thought going through your mind that caused you to decide to quit smoking, to go against what your body thinks it wants, and if you are truly a strong person, you will not need to do what your most banal desires tell you.
Keep in mind that it is very possible, simply by resisting all desire to smoke, not to smoke. This means that if you do decide to smoke again, it's because you think that you are unable to cope with the unpleasantness of quitting, when clearly it is possible. No matter how you look at it, you're smoking another cigarette because you believe that you are weaker than the cigarettes, not because the cigarettes are stronger than you.
I have my doubts as to the value of certain products and approaches to quitting smoking such as nicotine chewing gum, patches, therapy, etc. Perhaps they are all effective to an extent for some, but all of these make the basic assumption that a person can not quit smoking on their own. They promise to make the person able to quit smoking, to make it easier.
If you think that you as a person can't hack a quit without "help", you probably aren't going to succeed. Thinking you can't is the barrier. Yes, you'll feel shitty. Yes, you'll be irritated. Yes, you may get a headache. Yes, you might have a slight urge to kill other people. But you don't NEED to smoke again. All of these symptoms are irrelevent, temporary, transient. They will go away if you are focused on your higher goal of quitting smoking.
Just fucking do it, and when you succeed, never have another puff again in your entire life.