Opk best time to take them

I have never used opks but I ordered 50 cheapies off amazon on the 9th they said they would be here on the 11th so when they get here granted according to glow I'm only on day 2 of my fertile week I just want to know when I need to BD cause my SO works late most of the week and is very tired when he gets home so we usually only do it once a week so I'm hoping if I can hit my peak then I can persuade my SO into BDing but like I said I'm new to this I know that you don't have a positive opk until the other line is just as dark or darker then the control line I have learned that off of here... im just not sure when's the best time to test so please share your info with me.. thanks 😊😊😊