Master Your Calendar
The calendar is a widespread organizational tool because everyone understands perfectly well what a calendar is. Calendars have always been with us. They were used by our parents and grandparents. When I was a kid, we had a calendar hanging on the kitchen wall where my parents wrote things to do on some of the days, and circled important events in red. I remember my grandfather had a similar calendar in his office, and he would religiously cross off each day that ended with a big “X”.