Eleena - I was paranoid about missing my window (I did last month) and I sent atomic a long message about which days to DTD and how to execute the OPK and every 4 day method, etc, and she gave me great advice. The entire point of the every 4 day method is to not do OPK, not plan, and not think about it. It seems you are a planner by nature (as I am) and I think for me this month just picking a random start day and just BD every 4 days without thinking about it has been great. I would either do the every 4 day method as intended (without doing OPK) or just BD once during the month when your OPK seems nearly positive (or use a smiley face style to help you confirm). It seems you are over thinking things.