Advice plz

I have PCOS got diagnosed at 26

I'm 28 & have a 10 yr old

Got on birth control for a yr then stopped because my and bf wanted to ttc, periods stopped after that & i was told i don't ovulate and most pcos patients are able to at least have one child before infertility starts

Was prescribed Provera to take 9/11-9/15 got my cycle on 9/19

Started 2 2.5mg pills of Letrozole on Cd3-9 and told to bd every other day starting on cd 10 and monitor ovulation with opk test strips. Thats it. I'm so confused, idk how to track ovulation. I use the strips but idk if im missing important times of day or peaks i just don't know. It says I'll ovulate between cd 12-17 but how would I know besides the strips? Do you always get a sign? Especially with having pcos and having high lh anyway. Help plz!