FleetOps has a list of pre-built gadgets in the gallery. They are available for you to use, when you need to create a new dashboard or add a gadget to an existing one.
On a new dashboard:
Open any new or empty dashboard
Click 'Add Elements'
Pick 'Add gadget from gallery' and click 'Add'
On an existing dashboard, that already has some other content:
Open the dashboard
Open the dashboard menu in the top right corner of the screen
Choose 'Add visualization' -> 'Add gadget from gallery'
Note: Only stand-alone dashboards can be edited this way. Read how to edit dashboards created from template
This option opens up the gallery containing a wide range of pre-built gadgets which can be edited before adding it to the dashboard
Note that for performance reasons, visualizations for each gadget only load as your mouse moves over them.
Filter by chart type & dataset to narrow down the options or use the search functionality to search for a gadget
Select the gadget and click 'Next'
Optionally set the default date scope, run time / scope filters, comparison option and drill down. Read more about editing gadgets
Click Save
Resize the gadget by clicking and dragging the bottom right corner and move the gadget to the desired position using the drag handle on the top left corner
Click Save on the top right corner of the dashboard canvas to save your changes.