Use the References graph to see how tables are related to other tables through Foreign Keys.
When opened on multiple tables, the graph shows all links between the tables; you cannot choose to show inbound or outbound relations since all links are both outbound (from one table) and inbound (to some other table). You can however exclude unreferenced tables and/or manually select which tables to include on the graph.
To zoom in on a specific table, you can also view table relationships for a specific table.
Removing details and turning on highlighting to focus on certain aspects of the schema can be quite useful, especially if you choose to export the graph to discuss it with someone else.
Changing the layout, reducing the number of tables and suppressing some information makes it easier to focus on structure.
Check Viewing Table Relationships section for information about the references graph showing references for a specific table.