Who wouldn't like to write a hit song? You would earn fame, fortune, adoring fans, trips to awards shows, celebrity gift baskets, a place in the parade and so on. Yes there would be the occasional problems with paparazzi, but that seems like a small price to pay. .
So how do you write a hit song? In the following video, David Grohl of Foo Fighters suggests creating a chorus that would fit on a bumper sticker:
Now that you have the words, you need the melody. Consider using four simple chords: