If you need to create a lot of similar widgets (e.g. one widget per floor of a building), you can use the duplicate option.
Step by Step Guide
Creating Multiple Widgets
Find the widget in your dashboard and click the gear icon
Clicking Duplicate will create a brand new Widget and will open the Sensor Configuration screen (see 2. above).
You just need to change the list of sensors, or the date, and click Save.
A new widget has been created - now rename it, and you can move on to the next floor or building.