Q: How do I draw a coverline when fertility charting?

A: Follow these steps to draw a coverline on your BBT chart:

1. Identify a temperature that is at least 0.2 or two-tenths of a degree higher than the previous six days.
2. Highlight those previous six days.
3. Find the highest of these six highlighted temperatures.
4. Draw a straight line that is 0.1 or one-tenth of a degree higher than that of the highest of the highlighted temperatures.
5. This line is your coverline.
6. The coverline should run straight horizontally across your chart.