Charting your BBTs is easy. Basically, what you are doing is taking your temperature first thing each day and plotting the temperature on a chart.

What you are looking for is to see a shift of at least .4 degrees Fahrenheit after ovulation making your chart biphasic (showing low temperatures before ovulation in the follicular phase, and higher ones after ovulation in the luteal phase).

• Take your temperature first thing in the morning before you get out of bed  
• Try to take the temperature at as close to the same time each day as possible
• It is best to take your BBT after a minimum of 5 hours sleep, and at least 3 in a row is preferable.
• You can take your temperature orally, vaginally, or rectally -- just stay with the same method for the entire cycle.
• Plot your temperature on your chart each day: What you are looking for is a temperature shift of at least .4 degrees over a 48-hour period to indicate ovulation.
• After you see a temperature shift for at least three days,   you can draw a coverline between your follicular phase and luteal phase temperatures.  
• Look at the chart at the end of the month to analyze what happened.
• Chart for a few months and look for patterns.
• If your temperature stays up for 18 days or more after ovulation and is a typical biphasic chart