They help because otherwise you have no idea when you're going to ovulate. Most women don't know this anyways, but can have a general idea because their periods are regular. In your case, you need something to tell you when you're about to. That's what these do. Ovulation Predictor kits show a surge when your body is about to ovulate, and charting your Basal Body Temperate will show a slight temperature spike when you're about to. Both of these together tell you when the best times to have sex are.
Yeah I'm trying to use these charts.. I'm not sure how its going to help.? with how they work in to helping.
It just means you have irregular periods and will ovulate randomly. I have really bad irregular periods as well. The best ways you're going to know when you're ovulating is to use OPK's and charting your BBT. You could keep trying without doing either of these of course (I never tried to get pregnant and after 8 months of unprotected sex it happened on its own) but it could take a lot longer than you like.