Here is a step-by-step guide on how to write a chorus:
1. Figure out your song's statement.
2. Start with a chord progression or beat.
3. Build a melody.
4. Incorporate rhyme and repetition.
5. Let it rest.
6. Edit your work within the context of the whole song.
7. Repeat as needed.
This is just a basic framework to get you started. You can experiment with different chorus structures, using the title at the front, at the back, or both. Be open to new titles emerging from the writing as you stack lines. Try a four-line chorus, then expand it to six lines. Add a seventh line to a six-line chorus and listen to how it sounds.