About the technique itself, you can see here.
This technique of periods uses 3 levels:
- Each planet is given 10 years and 9 months;
- Each planet is given months equivalent to small years;
- Each planet is given a period determined by the Valens system (proportional division of the days of the planet).
The planet from which the dial starts can be selected from the context menu.
The Alexandrian year is used - 360 days.