Assassin

Kill people is all you have to do to become an assassin.  If you want to get paid for it, that's another matter, and something you have to do in secrecy, not just post an ad on Craiglist.  There are many targets already with public bounties for their deaths, such as Salman Rushdie and Osama Bin Laden if you want to work on speculation.

Personally, I think it is a bad career choice, but the pay is sometimes excellent.  The bounty on Bin Laden is millions of US dollars. 

The only way I can think of is if you are born into a family of assassins . You might really need the money and then you are raised into doing such stuff.

Hi,

   Why ask this kind of question?  Do you want to kill someone at 14?  That's not a good goal.  Ask your parents what you can do to be productive.