Hi,
It's nice to know that you are interested in changing bad habits.
If a person is aware of the negative consequence of pursuing such negative habits, half the problem is solved. The success of techniques like hypnosis depends upon the level of suggestibility of the individuals. Hypnosis is becoming obsolete. What I would recommend is that one should take conscious steps to put an end to such things.
I feel that for changing habits, three steps are involved: awareness about the negative consequences, steps to be taken - interventions, and finally sticking to positive habits. For all these, one needs support from society.
Individuals should either stop such habits all of a sudden or stop them step by step. I would suggest the first one. During the initial days, one may find it really difficult to abstain from smoking. What you can do is, if you are really finding it difficult, then you can have Wrigley's or cloves/cardamom (be sure that you don't develop an addiction to the substitute). If it is during a tea break or so where you usually smoke, rather than going with friends who smoke, you can definitely take initiatives to have tea with others who don't smoke, thereby improving your health and interpersonal relations - always think on a larger perspective - in essence, avoid tempting situations. If you think that if I take one puff nothing will happen, then my friend, you are wrong!
Even after taking conscious efforts, if you are not able to make any changes, you should definitely go in for some professional help. There are many de-addiction centers in Kerala - especially in Trivandrum.
During this change phase, one definitely needs the support of the family. Above all, you should have the willpower. Changes will not happen overnight; strive for it, and definitely, you'll achieve it.
All the very best to you!