Now the best way to get someone to quit smoking, is to get very annoying when they do start to smoke in front of you. This way they mentally prepare themselves for the worst, and are well aware of the fact that if they smoke around you, they are in for a rather unfavorable trip.
Throwing water at them, or splashing them with water every time they light a cigarette up seems to be a great way to go about things. Not only is it rather annoying, but it will also put out the lit cigarette, which serves all your demands.
Do a financial analysis
Now the one thing that will really convince anyone to stop doing something, is if they realize just how bad that is for them on a financial basis.
Smoking cigarettes is no easy thing to do, and it tends to cause people to waste a whole lot of money on the long run.
However, these people are far too foolish to realize just how much money they are wasting. As a result, if you simply calculated and told them how much money they could save, they might seriously reconsider their addiction.
Now sometimes the simplest way to go about things is to talk about them with your friends. Since you are friends, the person who you are talking to will be well aware of the fact that you would never lie to them. This is why you can simply talk to them and tell them just why smoking is not good for them.
If they are good friends of yours, they will go on and quit right away, as opposed to arguing over it.