How do you report hours that vary week to week? - 20 weeks in

My hours change every week at my new part-time job and I am afraid of reporting wrongly. This is my first time dealing with any of this. Pay posts on a different day from when I work. Did anyone get an overpayment notice from a mistake?

Thanks for writing this out. I went through something close to it 11 months ago, and it got easier once I kept a simple log of every call and form.