Can I just ask why you are planning to start smoking? It just seems to be a weird thing, to plan and do something like this.
I had my first cigarette when I was 9 and then started smoking properly at 11. I then stopped at 23 and have just started smoking again. Smoking can relax me, is great when drinking and after I've eaten food, it's also a social thing to do.
The bad sides (which definitely outweigh the good), it can kill, it is expensive, it makes you stink, it can make me feel ill and it is getting harder to smoke places these days.
If you're on about smoking weed then I can understand you planning for that, I personally don't like it - it does nothing for me, it makes me withdrawn and sometimes paranoid so I have not smoked it for years. If you do smoke it make sure you don't have too much.