When to start OPK's

[FlowerFairy]

I know this has probably been asked a million time but can someone tell me the best time to start doing OPK? I have a 27 day cycle and my AF lasts 4 days. Today is CD5. Also when is the best time to POAS? Not done them before and want my BFP this month!!

Massive thanks in advance x x x x

 

[Green Lady]

According to the chart I have, on a 27 day cycle you'd start testing on CD 10. Usually 11am to 8pm is recommended for testing times, though you should always test the same time of day.