What you need is an ovulation predictor kit. Follow the directions for your optimal times. You also might try having sex every other day or every third day to increase the sperm count. Sperm can last inside you up to three days as viable sperm, so if you ovulate even three days after you have sex, you can conceive.
Some people just have it a little harder than others, especially if you've used birth control before. If you have been on birth control, it can take a year to conceive, so since you've been trying for a year, act like you are just starting out if that is the case.
After sex, don't get up right away and have your partner elevate your hips. You can even buy a special hip elevator pillow that is designed specifically for women who are trying to conceive.
Until then, don't worry and lower your stress level about it (because lower stress will help you conceive) and just try to enjoy trying to make the babies...there isn't going to be much time to do that later on with little bundles of joy.
The very best of luck!