H.1.
You are most fertile in the 24 to 48 hours before you ovulate. If you're not sure when you're ovulating, instead of using your horniness level to guess :p - go get some ovulation tests from the dollar tree. $1 a piece and when you think you are getting close to ovulation you take one per day and it will tell you when you should have sex to get pregnant. I used these with my son (after a few months of just guessing and trying) and got pregnant instantly. :)