How to track ovulation and not get pregnant

Hi all,

I stopped taking my birth control pill last night. I do not want to get pregnant.

Question.... for those not on birth control, how do you track ovulation? I haven't had a 'proper' period for as long as I can remember, just spotting for a few days... hopefully it returns so I can have some kind of idea. But until that happens, how to know when I'm ovulating? And how to track that going forward in the long run?

Thanks