Charting your BBT can be beneficial, but only to confirm that you are ovulating. After several months of charting you could get some idea of approximately when you ovulate, but for the first 2 or 3 it can be difficult to see a predictable pattern. I love to chart and still do even though I don't need to. I get personal satisfaction from knowing that my body is working correctly.
The ovulation predictor kits detect the LH surge that occurs before you ovulate. The majority of women have success in using OPKs, although a few will get an LH surge but not ovulate. It can give some women a false sense of their body working correctly. With that being said, I have had good luck with them. They will give you a 24-48 hour warning that you are going to ovulate soon. I prefer the Clearblue Easy Ovulation tests, that are about $25US. (BTW: They work by peeing on a stick -- you look at the lines about 5 minutes later and determing if you are ovulating based on the darkness of the lines that you see. The instructions included with the kit will be quite thorough.)
Better than an OPK is to have regular sex! I think it's a good idea to have sex every other day until you get a positive surge on the OPK, then have sex 1-2 times daily for the next 3 days. My fertility specialist specifically recommends having sex 2 times daily during the most fertile time.
Wishing you the best!
Irregular Periods & TTC 
Linear Mode
