When to start testing with OPK?

I have PCOS - however, got my hormone levels checked & my ovaries and everything are perfect; within normal range and it is confirmed that I ovulate. My doctor gave me the go ahead to test for ovulation but I'm not exactly sure when to start? I'm on cycle day 5.

I have been pregnant twice - one miscarriage after a year of trying and then conceived my son naturally 4 months later with a bfp at 8dpo. We're now ready for baby number two.

Periods are somewhat regular 28-31 day cycle. Mostly 28 though. It's mainly late when I'm stressed.