BBT & OVULATION TESTING ADVICE HELP!

Katy • 27, Married, Boy Mom to Thomas John Herron 💕4💕12💕23💕

Im finally going to start charting this month, but idk what kind of bbt thermometer is best or where to get one without breaking the bank. Also I want to start using opk but again idk how to use them or which ones to get. HELP ME!