OPK question

Kim

I need some help. We have been TTC for 7 months now, and after AF was a week last last month (most likely due to stress of my father's health concerns), I decided to go all in and get some OPKs and start tracking my BBT to make sure I am getting the most accurate calculation of ovulation and not just depend upon CM and going off my glow calendar.

So my question is, when do I start using the OPKs?

Thanks in advance!