Cold turkey might work for some people but I always find it easier to do things in steps.
I'm more lenient on myself but I have lines that I never cross.
I quit drinking soda and eating fast food this way. With soda, I used to drink 3 times a day(insane, right?), the first three months I made a rule to limit to only once a day. I never broke this rule and the one soda a day was really a relief at first but then it became normal.
Then during the summer I made a big jump to only drinking soda twice a week on the weekends. It was hard as hell for a month but then once the school semester started again I forgot about how hard it was.
Then from there I just forgot about drinking soda, I didn't really want it that much anymore.
If you quit cold turkey you might find yourself developing another bad habit to compensate. Give yourself space to adjust, but never break your own rules. That works for me at least.
I find for cigarettes it makes them more "valuable" and I cant wait to have my next one when I set myself rules to just smoke x amount of cigarettes. Which made me more addicted mentally to them.
I will see.
As more you are addicted as more you have to gain is one of my mantras atm.