Pregnancy:
Basal Body Temperature and Cervical Mucus Chart

The best way for you to detect ovulation is to keep a daily record of your basal body temperature (your temperature when you wake up in the morning) and the texture of your cervical mucus. You need to chart your cycle for a few months so you can recognise your pattern and have a better chance of predicting your most fertile days.

How to check your temperature:
Start keeping track of your temperature on the first day of your period using a basal body thermometer, (you can buy one at all chemists) which shows minute changes in your temperature. Take your basal body temperature at the same time every morning if you can. When you have done this mark it on a chart (shown below).

It's helpful to chart your temperature for a few months so you can see whether there's a pattern to your cycle. If you're sick or fail to take your temperature immediately upon awakening, any pattern you find may be inaccurate. Thermometers that remember the last reading are helpful if you tend to go back to sleep after taking your temperature.

How to check your cervical mucus:
It sounds foul but it`s got to be done. There are 3 ways you can do this: using toilet paper or your fingers across the opening of your vagina, wearing a panty liner (which is sometimes hard to detect) or inserting your finger into your vagina. Note its consistency. You may also want to monitor its texture throughout the day. Read more on monitoring your cervical mucus

The two together:
You should notice a rise in your temperature signaling that you have ovulated at the same time your mucus will look and feel like egg white. When the two coincide this is your time to start making babies.

Here is an example chart.