Change one chord to it's relative minor/major.

Offset the rhythm.

I mean, apart from the fact that most pop songs kind of sound the same. Start there, and you'll discover more ways to make your song more "you". If you feel like something you wrote sounds too similar to another song (unintentional or not), play around with it: Lower or raise a note in the melody. 13 Songs That Sound Suspiciously Like Other Songs. And sometimes, songs sound so like other tunes that things get heated and lawyers have to get into a room and work things out, whether the similarity is intentional or not. Joe, Kevin and Nick have been teasing the release of 'WHAT A MAN GOTTA DO' for some time on social media, starting with them posting the eye emoji, each. Think of ways to use "addition by subtraction".