I am trying to conceive for more than 2 years. I have never tried to plan intercourse according the ovulation. My sister told that it is the best thing to do in order to increase your chances of getting pregnant. I am interested what is the best way to determine the exact day of ovulation, taking ovulation tests? or is it more accurate to do an ultrasound every day?

Please tell me your experience of how you were determining the exact day of ovulation.
Thanks a lot in advance,