Give every section a job
An intro establishes identity, a verse carries detail, a pre-chorus creates pressure, a hook releases or confirms it, and a bridge changes the argument. Name the function as well as the section.
Create contrast without changing songs
Keep the core identity stable while changing density, register, rhythm or harmony. A verse can stay dry and narrow before the hook opens the vocal and widens selected support.
Design transitions
Use a fill, dropout, breath, pickup, reverse texture, bass mute or underlick turn to announce movement. The transition should prepare the next section rather than decorate the last bar.
Make repetition develop
Return the hook with one meaningful change: stronger choir harmony, altered ad-lib, denser hats, higher motif register or a shorter final line. Familiarity carries the identity; variation carries the story.