Hello,
To quit smoking most important thing required are persistent motivation, support and good detoxification measure. If tried leaving on own you may face withdrawal symptoms. There are various detoxification treatment available with high success rate.
Next Steps
You can consult me for further help.
Health Tips
Remember craving for smoking is hardly for 30 minutes and if you can overcome that 30 minute by drinking water or diverting your mind in some other work I think you will be able to control craving.