Opks!

Tee • Mommy to an angel baby born on January 22, 2014 at 20 weeks. #AidenLewis BFP 3/1/2015 BABY GIRL DUE 11-5-15
So I'm on cd8 and I think I'll start using the opks today. So is there a specific time to use them? Do I use morning urine or is any urine fine? Do i test until i get a bfp? Help me plz lol!