John Lennon explained "I'll Be on My Way" "was early Paul." Credited to Lennon–McCartney, Paul McCartney wrote the song in the first half of 1959. Author Todd Compton attributes it to "McCartney–Lennon." McCartney wrote the song on his first guitar, a Framus Zenith acoustic guitar. In "The Beatles Anthology", McCartney recalls, "All my first songs... were written on the Zenith; songs like 'Michelle' and 'I Saw Her Standing There'. It was on this guitar that I learnt 'Twenty Flight Rock', the song that later got me into the group The Quarry Men." When first written, the song had little beyond its melody. The song was fleshed out years later after the Beatles added it to their live repertoire.