You should buy or check out from the library a book called "Taking Charge of Your Fertility" by Toni Weschler. Most women here, including myself, treat is as a bible of the female body. It will teach you everything you need to know about charting and more. There are, of course, ovulation tests, which will let you know that ovulation is about to come. However, they do not confirm that ovulation has indeed occured. Also, charting will tell you a lot more about your body. For example, if you leuteal (post-ovulatory) phase is long enough for implantation of the fertilzed egg to be possible.