Stop smoking tobacco and start vaping e-liquid. You get pharmaceutical grade nicotine and the feeling of something in your lungs without any of the nasty cancer causing chemicals you get when inhaling tobacco smoke.
I started smoking at the age of 14. I have smoked at least 20 cigarettes a day since then. While living in China I was smoking 50-60 cigarettes a day for a three year period. I am now 30. 2 months ago I got my e-cig in the post and haven't looked back.
Google it!