These charts are explained on the Calendar page. If you print up each chart separately, you can cut them out and put them together to make a sliding calendar. The days of the week will appear in the window above the days of the month. (To print a chart separately, drag the mouse across the chart to highlight it. When you print, select "selection" when it asks you what to print.) I recommend printing on cardstock. If you print on paper, you may want to glue it to cardboard.
To make the calendar, cut out the charts. The two charts at the bottom of the page tell you what day each year starts on. You may want to print both of them together and cut them out as one piece, or only print one of them. Cut out the window on the chart that has the numbers 1-31 arranged like a traditional calendar page. Place it back-to-back with the year chart you have chosen to use, and tape along the two sides. This will form the sleeve. The front of the sleeve is shorter than the back. The chart with the days of the week fits into the sleeve. You may have to trim the sides a bit to get it to fit. Using the instructions on the Calendar page, decide which day of the week that month starts on. Slide the day-of-the-week chart so that the row beginning with that day appears in the window. It now makes the headings for the days of the month below.