TTC w/ PCOS

Hey ladies! So last week i got the okay from my doctor to stop taking my birth control, and i could start TTC. I’m so excited! 🙌🏼😩 she’s had me on metformin, and wants me to continue that. I just got off my period on Thursday. My question is when do i need to start doing OPKs? I’m praying for my rainbow baby! 😩😍💖