If Georgetown's Bluebook Guide does not adequately address your questions about a citation, The Bluebook is available as a Ready Reference book at the Guerrieri Academic Commons, just remember, ready reference books cannot be checked out, so you'll need to use it while in the library.
A legal citation's format will change based on several factors such as the jurisdiction, court, and type of case. But citations do have a few basic parts:
Both HeinOnline and Google Scholar shows all the information you will need to create a legal citation right under the case name. The benefit to Google Scholar is it doesn't default to also searching for law review articles, so it may be quicker to use Google Scholar for citation purposes.
This image shows the search results for Brown v. Board of Education. Under the search result there is a line that reads, "347 US 483, 74 S. Ct. 686, 98 L. Ed. 873 - Supreme Court, 1954."
I can see that my citation for Brown v. Board of Education has three different reporters listed, the unofficial reporters Supreme Court Reporter (74 S. Ct. 686) and the United States Supreme Court Reports Lawyer Edition (98 L. Ed. 873), and the official reporter, United States Report (347 U.S. 483). Always use the official report if it has been published. My citation for Brown v. Board of Education should therefore read:
Brown v. Board of Education, 347 U.S. 483 (1954).