How do you report hours that vary week to week? - 25 weeks in

I picked up part-time shifts as a data-entry clerk and I am confused about how to report them. I worked as a data-entry clerk before this. Pay posts on a different day from when I work. Do you report when you earned it or when you were paid?

Report honestly and keep your stubs. An honest small error is much easier to fix than a missing report.