To Edit your Dashboard Widgets click into the three circles on the top-right of the widget container.
Then, select Edit from the options. (Note that you can also Delete the widget this way.)
This will then take you back to the steps of creating a widget where you can then make the required update, remembering to Save & Exit when complete.
To reorder your Dashboard widgets, click the move icon also located at the top-right of the widget container:
Then, drag the widget to the required location on the Dashboard page.
If you have multiple widgets within your Dashboard this is also how you can change their order on the page.
You can also expand or reduce the width of each widget, by clicking the icon on the bottom right corner and dragging it right or left.
Item List Widget