In an activity diagram, guard conditions indicate different possible transitions from an action state. If one of these transitions leads to another decision, you can represent that decision with the traditional diamond shape. A decision must have one or more incoming transitions and two or more outgoing transitions, each labeled with a distinct guard condition.
Name a Decision shape and add other property values
Open the element's UML Properties dialog box by double-clicking the icon that represents the element in the tree view or the shape that represents the element in a diagram.
Control which property values display on a shape in a diagram by right-clicking the shape, and then clicking Shape Display Options. In the UML Shape Display Options dialog box, select and clear options to display or hide property values.