You can display each interface directly realized by a class as a 'lollipop' style interface node, which protrudes from the left-hand side of the class. Connectors can be directly attached to the node, indicating usage of the interface part of the class or component. See the example below:

In this example, Class2 realizes Interface1 and Interface2. This is represented by the interface nodes protruding from the left hand side of the class. Class1 is dependent on these two interfaces, which is shown by the dependency arrows linking to the nodes.

To show nodes for the interfaces a class realizes as in the above diagram, right-click on the class and select Show Realized Interfaces. This setting only applies to the selected class, and can be changed at any time.