You do not have to force it so, there is a method slowly .. first you have to reduce your smoking habit, then all you have to do is to do something that keeps you busy. that way you will forget the habit of smoking. and start with other substitutes like candy.
Its beginning feels difficult but after 3 months all will feel ordinary normal.
I was also a smoker and had left the habit 8 months ago.
good luck my bro