How do you get someone you like to break up with their boyfriend or girlfriend?

Im just a kid but i say what you do is, send i wanna break up with you letters to the boy you like at the end of the school day every day. Don't forget that at the end of the letters when you write the from part, put the boys gf's name and if you keep it up he'll break up soon. If his gf is like, reeealy obnoxious and up herself help him to notice that. It's more honest than the one above. Also hint in that you like someone but don't tell him who it is. This can make him jelous and if he already likes you he is more likely to breakup with his gf to see if you are still free. Most of all be yourself!!! Crack a few jokes, if your in highschool ask if he wants to go get a coffe, Hot Chocolate, ANYTHING!!!!!!! after school. If he sais yes YOU GO GIRL!!!!!!!!!!!!!! If no keep on trying