It took me a while after birth control to have any normalcy to my cycle, so I feel your pain. Maybe pay close attention to your body symptoms? My ovulation symptoms vary month to month, but the one thing that stays the same is **Okay TMI coming up*** the amount of vaginal mucus. Typically, when a body is preparing to ovulate we get a decent amount of clear mucus that resembles egg-whites. I really notice it the day before ovulation. You can try to look for that sign. If all else fails, if you did not want to track daily through BBT, maybe try an ovulation predictor kit. I get cheaper ones off of amazon. Some people like them, others hate them. I find they work just fine for me.
But I suggest that you start by looking for that sticky, egg-like mucus. When you notice it, make sure you are 'getting it on'! lol