ovulation

Best way is to buy ovulation prediction kits (OPK) from the drug store or walmart. That would tell you when you are going to ovulate. Also, you can track your cervical mucous. If its clear and stretches more than 8 cm and looks like egg whites then it means you are about to ovulate the next 2-3 days. Not all women see this Cervical Mucous though..So, best predictor is OPK.

If your period is like clock work, then count 14 days before your next period start date and +/-2 days from that date is your most fertile..but again cant exactly say ovulation will happen that day that month..