We create the Table for Federal Cases here
Click Tools | Reference | Table of Authorities
Here, we select Federal Cases.
If the desired type of authority is not present, it can be created by the Create button.
...by pressing Insert.
As with the Table of Contents, this lets the user know where this Table of Authorities will appear.
Now we repeat it for each of the five tables on this page: Federal Cases (here), Other Cases, Federal Statutes, Other Statutes, Other Authorities. These almost always suffice for me, but you may want to divide the authorities in other ways.
All five fields are set up for Tables of Authorities.