How do you report hours that vary week to week? - what worked for you?

I picked up part-time shifts as a marketing coordinator and I am confused about how to report them. I worked as a marketing coordinator before this. The form asks for gross earnings, which I do not see until later. Did anyone get an overpayment notice from a mistake?

I estimated and then checked my pay stub. When there was a small difference I wrote to the agency to correct it.

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