Quick question or ten on OPK best practice?

[JaneEyreWasASellout]

Would anyone be so kind as to remind me best practice for opk cheapies? Can't remember the details....... but have just ordered some.
My frazzled braincells tell me to check mid-morning and mid-afternoon or late afternoon? Otherwise you night miss the surge? Right? With pee that I've been holding for a bit? Or doesn't it matter? Start on CD8? 10? 12? As dark or darker? And then that means that I'm due to ovulate....... in the next 6 hours? 12 hours? 24 hours? Arghlghl!
TIA. I need coffee. I should stop drinking coffee.

Depends on your cycle length, for a 28 day cycle its usually recommended to start on CD8. If the OPK is very clearly negative in the afternoon, I wouldn't personally bother with a second that day. But some people have a quick surge so totally up to you really.

At least a 2 hour hold with no liquids is best. A positive OPK is as dark as or darker than the control line (but some people never get that dark, so go by your own signs). Then you can expect to ovulate 12-48 hours later. Best to get DTD when your OPKs are almost positive, then on the day of the positive and the next day.

Thank you MrsG!