The best way to get a woman pregnant is to have sex with her around the time that she ovulates, or when she releases an egg. This typically occurs in between her.
An active sex life is all most people need to conceive. If you know when you ovulate each month you can give yourself the best chance of getting pregnant by having sex in the days leading up to ovulation. Continue having sex during ovulation. After this your fertile time will be over for that cycle.