I really don't agree with u girls.!
I even don't agree with what they say about bdin every other day.
I read that the egg is only alive for 12-24 hours, so ur could be 12 hours. thats what i assumed for mine, and they say that sperms live in u for about 3 - 4 days. but this fact is not true for all. some one have a ph that don't allow the sperm to live long. or maybe the sperm is not that strong.
what i did is bding every day. but on ov day i db twice for two days every 12 hours, it was frustrating and dh didn't like it coz it was timed! it was hard work but it did work.
I did lift my legs as well, not sure if it was another reason but i did it.