Smoking is bad for you. Thankfully, less than 17% of Australians now smoke. This is one of the lowest incidences in the world.
Smoking kills. It is like playing Russian Roulette. Not everyone who smokes will die from it, a lot of them do. If you smoke, this is the biggest change you need to make in your life. All of the other changes you make in your life will amount to far less, unless you give up smoking.
Like any addiction, it is difficult to give up smoking, but there are people to help you. You should start with Quit Australia- http://www.quit.org.au/
You should consult your general physician about other medications and patches available to you in your journey towards being cigarette free.