Write a list of the reasons why you want to stop, and keep them with you. Refer to them when tempted to light up.
Set a date for stopping, and stop completely. (Some people prefer the idea of cutting down gradually. However, research has shown that if you smoke less cigarettes than usual, you are likely to smoke more of each cigarette, and nicotine levels remain nearly the same. Therefore, it is usually best to stop once and for all from a set date.)
Tell everyone that you are quitting smoking. Friends and family often give support and may help you. Smoking by others in the household makes quitting harder. If appropriate, try to get other household members who smoke, or friends who smoke, to stop smoking at the same time. A 'team' effort may be easier than going it alone.
Get rid of ashtrays, lighters, and all cigarettes.