Time It Well
You should always know where you are in your cycle and have in mind when you are most fertile. Timing is very important with conception, and you need to try to conceive one or two days before you ovulate.
Try, as much as possible, however, to keep your sex life interesting and spontaneous. Stress and negatively work against your chances of conceiving.
A Few More Words
Make sure that you aren't using any lubricants while trying to get pregnant. They can decrease the sperm's ability to travel easily to the egg and may inhibit your chances of conception. Try to keep your lives as relaxed and stress free as possible while you are going through this process.
Perhaps add some bonding time into your lives, including yoga, hydrotherapy, a couple's night out, and more. Conception doesn't have to become a chore or a job - it certainly wasn't intended to be an obligation!