If you are worried there are several things you can do, (asking mn is not going to tell you!!!)
The first thing you can do, would be to make sure that you are fit and healthy. Make sure your weight and fitness are optimal before ttc. Start taking folic acid 3 months before ttc too.
Next as NotTryingNotTo has done, you could track your cycle for a few months if you are not using hormonal contraception. Look at the website fertilityfriend.com for advice on tracking your cycle.
You could go to doctors and get blood tests to check your hormone levels, this would be best after tracking your cycle, so that the day 21 test can be done 7 days post ovulation rather than day 21 of your cycle, to ensure you get a more accurate result. Day 3 tests do not need the day of ovulation to be known.
You also could make sure that you are not basing infertility on your shoulders alone, by ensuring that your dh has a sperm count done if after 6 months or a year of ttc, you have not become pregnant.
Remember that with each cycle there is still only a 20% chance of pregnancy, so it is not that high, even without fertility issues. Have sex every other day if possible, not just when you think you are fertile. If after a few months this has not worked, follow the sperm meets egg plan, but don't do this at the start of trying, as it can become a huge stress on the relationship.
Most importantly is to try to not get anxious about it before you even start, try to let those first few months of trying be fun! (I would suggest not letting your dh know when you are "fertile" or "ovulating", as many men find this off-putting, as it makes them feel under pressure to perform, and often has the counter effect!).
Remember that most women do not experience infertility, and that most conceive within a year of starting to try. The odds are in your favour, in real terms, and until proven otherwise think of yourself as fertile!
I hope that when the time comes for you to start ttc, that it happens quickly for you.