Ovulation refers to a period of time in a woman's menstrual cycle, usually about 14 days before her next period. During this time, a woman's eggs mature and are released, which is very important if she wants to get pregnant.

1. Measure basal body temperature: The body temperature measured when women wake up every morning can be used as basal body temperature. On the day of the menstrual cycle, the day when the basal body temperature is the highest is the ovulation period.

2. Observe symptoms: Some women may experience symptoms during ovulation, such as breast swelling, nausea, headache and diarrhea. These symptoms may disappear within a day, so watch for them and record them.

3. Use a pregnancy test stick: A pregnancy test stick can test whether you are pregnant during the ovulation period. They usually take several days to produce results, so it is best to test after the cycle is over.

4. Refer to the calendar: A calendar can help calculate the exact date of ovulation. On the first day after your cycle ends, subtract 14 days from the date to calculate accurate ovulation.

While the above methods can help calculate an accurate ovulation date, they are not always accurate. Therefore, if planning to become pregnant, it is best to consult a doctor or professional advisor for more accurate advice.