I had my 3 at 35, 37, and 39. I thought I was over the hill, because my husband and I weren't even careful for a couple of years before #1 but nothing happened, and then one day POP, and the next two were mysteries because I must have been uber fertile after one.
Anyway, my gyno said:
On the 11th day after your period STARTS, have sex. Abstain for a few days before hand, because you want a nice big load (sorry). Then have sex EVERY OTHER DAY for the next 7 days.
This will span the entire ovulation. Don't worry about your fertility until this has failed for a year.
We weren't trying on purpose for #1, but it did happen to be in this schedule when I conceived. We were reunited after a long separation and had sex the 11th day after my period started and boom. Pregnant. Or it could have been one of the following days :) But it was that month.
My kids are all healthy, the pregnancies were all fine, and most of my friends started trying for #1 around 40. My close friend just had her youngest at 42.
Being an older mom rocks, because you've seen a lot of kids grow up, and you don't get sucked into the contemporary child raising myths.