Improve legibility by showing only that information in your calender which you actually need.

1. Click on  Data sources in the toolbar to open the picklist.
2. Move the order of the data sources by holding down the left mouse button (drag-and-drop).
3. Select one data source by left-clicking (hold down the Ctrl key for multi-select) and click on  Apply.
   Ex: Show only events and shifts
4. Click on each data source to set further options such as:
   1.  Filter
   2.  Hide if empty
   3.  Standard list or  Custom list.