PolicyMap is a database which has maps already created and you may also create your own with the data provided.
If you need to create a map within the American Factfinder (Census) and you need to customize (change the basemap, color, etc.), after you have created the map itself using some of the following data tools:
First, create you map from the Tiger Web. Reference their guide, How we map as well as Creating a Thematic Map Using TIGER/Line Shapefiles.
You can then select your basemap (2018 data is now available)
For help in using the products, see these tutorials:
Data Gems: How to map using the American Factfinder
Getting Started with OnTheMap (formerly Base Map Help), Census
Guide and Brochures, Tiger/Lines Shapefiles
How to download census data from the American Factfinder
Using data.census.gov Basic Mapping
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