Use a basal body thermometer
Take your temperature first thing in the morning
Measure before getting out of bed
Take it at the same time each day
Use the same method each time
Place the thermometer under your tongue, in your vagina, or rectum
Keep still and wait for the reading
Record the temperature immediately
Track it daily on a chart or app
Look for a slight rise after ovulation
Avoid alcohol, illness, poor sleep, and late nights when interpreting results