Tracking periods while breastfeeding

How do y'all track your periods? Like when they were going to happen. I'm not use to this spotting stuff. When I breastfed my daughter 3 years ago I still had my normal period. I want to track my period because my hubby and I are talking about trying in 2021 for a little boy. My normal period is 7 days long every 28-31 day cycles. After my postpartum bleeding I starting spotting on and off for 8 days. And then last month I literally spotted 2 times for a day each. Other than ovulation tests and quitting breastfeeding best way to predict periods. Thank you in advance ☺️