Start with a new-style spreadsheet.  Change the name of a sheet to Data.  Add columns (at least one for the complete address, plus others to use in the display and in filtering).

Open the file here:

Go to the Add-ons menu, hover over Mapping Sheets, and then click on Start Mapping.

In the right side-bar, identify which columns in your spreadsheet will be used for the title, for filtering, and for the locations.  Then click Build.  This may take some time to convert addresses into locations.  When it's done, click View to see your map.

Click on the pin icons on the left to add and remove data based on the Filter column.

The map that comes from my sample spreadsheet: