Cancer, heart attacks, emphysema, these are only a few of the major problems you could get from smoking. Not only can you get long term health problems, but it's also very unappealing. Don't forget that you'll also loose tons of money. Many of my family and friends have been through this problem. That's why I think to not smoke is the best advice I can give you.
First of all, having the habit of smoking isn't cheap. Say you burn threw one pack of cigarettes a day. One pack costs about, let's say, $2.50; times that by seven, then four, then twelve. It comes out to about $800.00 total. You spend your money on something that doesn't do you any good. I know I could get many decent outfits, (including shoes and accessories) for that price. Also you don't want to forget those hospital bills from the nights you weren't breathing well.
Those also add up. Now I know there's something much better that you could spend your money on than unneeded cigarettes and hospital bills, don't you?
Secondly, smoking can make you look very unattractive. The bad breath and terrible smell it leaves behind can make someone sick. The worst thing is that you can't do anything about it. Perfume doesn't cover the smell, and you'll always have the stinky breath I have this one friend whose mom smokes. One time I went over their house I didn't notice anything; but once I was home that night and my dad asked why I smelled so bad. Since no one in our house smokes, the smell stuck to me once I came home; you could smell the smoke left on my clothes. All I have to say is that it was not very pleasant.