1. Daily TrackingJane takes her basal body temperature every morning at the same time, before getting out of bed, using a special BBT thermometer.2. Recording DataShe writes down her temperature on a BBT chart or app every day.3. Pattern Over TimeAfter a few months, Jane sees this pattern:Her temperature is around 97.2°F to 97.6°F (36.2°C to 36.4°C) for the first part of her cycle.Then, around day 14, her temperature jumps to around 98.0°F to 98.4°F (36.7°C to 36.9°C) and stays high.This rise indicates that ovulation has occurred.4. Fertile WindowJane knows she is most fertile in the days before the temperature rise and the day of the rise.