Think. What do you want your song to be about? Write down a few ideas.
Come up with a common tune for your song. Repeating it will give you a base of your song, and it will make it easier to add lyrics.
Start writing your song. Words in a song are called lyrics. Think of lyrics that go along with the topic of your song.
Write the chorus for your song. Think of lyrics that go along well with your topic.
Write 2-4 more stanzas after the first chorus. You can repeat some stanzas from the beginning of the song.
Repeat your chorus.
Add a bridge. This is where you will bring all of your emotions and make the song the most tense. It can be a sad and dramatic bridge, a suspensful bridge, or just repeating your chorus again in a different tone.
Write an ending stanza.