Clear blue digital advanced... OPK

Ok, so I know you get a few days of "high" before your peak. My question is if the general rule is to BD every other day... What if you get a high and don't bd and than get your peak the very next day.. I know you would want to BD that night but would we be too late? What if we ovulated that night before on our off night?? I hope this makes since lol!!!! Any advise??