Creating a property holder

To create a property holder (UML class stereotyped as «Anything»)

Create a UML class (named "Thing" below).
Figure 1: A UML class.
Right-click on the UML class and select Stereotype.
Figure 2: Selecting the class' Stereotype shortcut menu.
Type "Anything" in the search box.
Select the stereotype "Anything".
Click Apply.
Figure 3: Selecting the Anything stereotype for the class.
The stereotype will be applied to the class.
Figure 4: The Anything stereotype applied to the UML class.