I combined a couple of methods:

- stop smoking in certain situations (no cigarette at the bus stop, no cigarette after lunch, …)

- allow myself to put out a cigarette halfway when I’m smoking. I lapsed and lit one, but that doesn’t mean I have to finish it.

- try to feel the downsides of the cigarette while smoking. The nicotine high mostly overrides this, but it’s possible to concentrate on the yucky feeling in your mouth, your lungs being burned etc.

- telling myself that I am sure I want to stop smoking at some point in my life so I might as well stop now.