OP, first of all if you smoke only one cigarette a day, I'm not sure what advice to give you. That frankly doesn't even sound like a potential health problem for me. All I really want to say is: keep it at one a day and enjoy

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Ok longish post, which I may add to now and then. This is addressed to people who are hardcore smokers.
Every person's quit (once you get into the research, you'll realise that 'quit' is treated as a verb and a noun in the quit smoking community) is different. What works for me may not work for someone else. That said, below are the best practices that usually work for a lot of people.
Don't try just one method to help you quit. In other words, there is NO '
"a serious way to quit smoking". In my experience, you have to used a number of methods simultaneously to make it work. In other words, just setting a date and time and then quitting on that date is mostly a recipe for disaster. The more different ways you try (at the same time) the better your chances of success.
The typical quit goes like this- I'm going to quit as of now, in one day, this weekend, etc. Even if you stick to the deadline, a few minutes/hours /days later you're back to smoking. This is because the nicotine urge gets to you.
What you should be doing instead is: Join a quit smoking forum, read a quit smoking book(s), do plenty of online research on hazards of smoking, see a hypnotherapist (if that works for you), tell your friends you're quitting, and anything else that feels right. In other words,
prepare to quit, don't just treat it as a single activity.
Look at it this way (since this is a cricketing forum)- most people can't just become top class athletes by only practising hard. They need to practice, get the right nutrition, do the right exercise, find coaches, develop mental strength and so on. Similarly, most people cannot quit smoking if they think they can 'just stop'.
Why should you research the need to quit? To internalize why smoking is bad for you (there's a huge amount of very convincing literature that goes beyond the 'smoking causes cancer/is bad for your body' thing). To understand how your quit can be threatened, by circumstances or friends who smoke, or old habits (example- smoking after a meal). To learn to recognize dangerous times (waking up, drinking) and places (bars) and situations (work stress, friends standing around chatting, parties)
Why should you join an online quit smoking forum (I was on an about.com site)? Because you need friends who're quitting at the same time, so you can share, vent and avoid common traps. You can learn from their errors, and you can move forward as cohort. I recall how we would check in daily (at first) to reassure each other that we were still smoke free. Then every two days, then every week or so (a year later) and so on.
I'm not sure which method worked for me- the forum, or the research or the hypnotherapist- but I do know that all of them taken together did work out.
The single most important advice I can give you is to read up. Read in particular "Easy Way To Quit Smoking", By Allen Carr. I was never a fan of help books- until I read this one. I'l tell you this is one of the most popular books ever written, and it has worked for many people. It was the best money I ever spent on anything, period. Just try it.
The other resource (among many online resources) I liked was
http://whyquit.com/
This is a guy in Chicago (now retired) who helped a lot of people give up smoking in the 1980s and 1990s. He has ported a lot of his techniques online for free. This is an excellent, excellent resource.
That's it for now, feel free to ask questions.