I definitely second the vote for Pre Seed, very good stuff. Eat well, sleep enough, drink lots of water... basically be as healthy as you can be (no mad diets, no excessive exercise etc). I take EPO from CD1 to O and Flaxseed Oil capsules from O to CD1 again (don't take EPO after O as it can cause uterine contractions which is what you don't want when a bean is burrowing!). I also take folic acid tablets and a Mum to be multivitamin. Timed BDing is supposed to be great but it can be stressful - try and take out as much stress from your life (easier said than done of course in this day and age). Above all, I would suggest not to expect this to happen immediately, it does for some but not others and putting unfair expectations on yourself at the moment can cause additional stress. Ultimately, this is about you and your partner making a baby from love, I've found it important to keep that thought forefront in my mind.
Best of luck!!!!