The rotate tool allows you to rotate elements of your project's geometry.
Rotating an object
Use the select tool to either click and draw a selection box over your geometry, or to select one (or more, using SHIFT) of an entity's constraint points.
Click the rotate tool (or use the R keyboard shortcut).
Click and drag from any point on the map to increase the diameter of the selection circle.
Move the mouse to either rotate the entire entity or the portions of its geometry that are joined to selected constraint points.
The Rotate Panel displays the current angle of rotation in degrees: