When should I start testing?

💜Marty🌼👣💫🐻❤️🌈 • Marty💜 Catherine💚Kane 6/09/17 Eli 7/13/05 💙Taelon 11/6/08 💙Miles 12/18/10 💙Daxton 9/2/13💙👼Nokose 3/7/19 - 6/2/19 💞🙏💔 🌈👣💜 Malani 🌼 Due 6/9/20

This is my first time using opks and I bought some clear blue easy at home tests. Glow says I ovulate on the 23 but Flo says the 20th.