When to take OPK?

Jessyca • Married On 6/8/17 Zoey James 6/29/18 Drake Parker 9/26/19

Hello Mamas alike!! I am using Opks for the first time this cycle. I am as of today on Cycle Day 10. My normal cycles are 28, however my last cycle was 31, which was very out of the norm for me. I'm curious as to what you experienced ladies think is the best time to start taking my Opks? Any advice or help is appreciated. !