I can only say what worked for me.
I smoked for about thirty-five years and at my peak lit about sixty cigarettes each day, I say lit as I would light one and take a few puffs then put it down as I worked, it would burn down and would immedaitely light another. At the end I suppose I was smoking about twenty each day, and actually smoking them.
Then I was diagnosed as diabetic, type II, and my doctor said diabetics were higher risk for strokes and heart attacks, and smoking doubled the risk.
I went home and thought about me and how I ticked. From experience I knew if I COULDN'T have a cigarette then I craved one, for instance if I ran out I would be pretty desperate and used to have to go to bed as I didn't smoke in bed. So to tell me, or for me to tell myself, that I could not have another cigarette would make me want one, I would be desperate for one.
Solution was NOT to tell myself that I couldn't have another cigarette, just that I would DELAY lighting the next one. The cigarettes and lighter are in the cupboard, they are well stale by now as that was March 2000. I am still delaying lighting the next one - but I know that I can if I want and that is enough for me. Some days I am tempted but I just say 'not yet' and the desire passes.