This is all paraphrasing, as I am listening to an audiobook, no subtitles, so here it goes...
Believe it and you'll see it!
All behaviors are preceded by thoughts.
Don't full yourself by thinking it is much easier to smoke or eat that chocolate.
In fact it is much harder to smoke: you have to go to the store, buy the pack, put it in your pocket, come home, get the pack out, pull out a cigarette, light it up, then go back to the store again, just to spend more money on it.
When you don't smoke that is all you have to do: simply do not smoke.
As for me, I don't do that anymore.