Step 1: Build a Map View, double-click on a geographic field such as State, Area Code, Zip Code, etc.
Step 2: Select the Filled Map Mark Type; the automatic mark type will show this type of view as circles over a map. On the Marks card, select Filled Map to color the geographic areas.
Step 3: Drag a Field to the Color shelf, define how the locations are colored by dragging another field to the Color shelf.