I smoked a pack a day for many years and despaired of ever being able to quit. A lot of my success in finally stopping is that my boyfriend, now husband, agreed to quit with me. For me it was crucial to avoid being around smokers.
Another thing that helped was to keep my hands occupied. I learned a simple, basic crocheting stitch and crocheted yards of yarn that served no purpose other than to keep my hands busy. It helped tremendously.
Drinking a lot of water also helped with withdrawal symptoms, why, I don't know.
If you are fortunate enough to be able to exercise, I'd recommend it, as much you can. It helped occupy my time and made me feel as if I were really getting healthier.
Quitting smoking could be the best thing you ever do for your health.
Benefits I noticed were much improved stamina, the elimination of my smoker's cough, better immunity, and a boatload more cash.