Click on the Edit tab to add new structure features, edit existing structure features, and remove obsolete structure points. Structure points are represented by icons with colored borders on the map.
Clicking on a point in the map will open a window displaying information about that feature. Use this window to enter missing information about a feature or update the information that is already there.
You can also add comments in the comment field if you'd like to list the sources you used to research your edits, list reasons for why you created or deleted a point, or note other information you think might be useful to someone reviewing your edits.
The different colors displayed in the Edit Status Key correspond to the colored borders around the icons in the map or the colored dots when you are zoomed out. Each color relates to the editing status of the point.
When zoomed in far enough, all structure features show up as icons with colored borders on the map: