To rotate a selection (assuming that a selection has been made), right click on the image, and choose Transform selection as before. A selection transform box will appear around the perimeter of the selection, with move handles on the sides and corners. When you see this box, right click on the image again, and a menu of options will appear that allow you to control the behaviour of your selection.

 

The next step is to choose Rotate from the list of available options. When you do this, you will see your mouse pointer turn into a small curved arrow when you move it around the outside of the box. If you drag your mouse clock wise, or counter clockwise with the curved arrow pointer, the box and the selection it contains will also rotate in the same direction.

When you have finished rotating release your mouse button, and the selection will be left in the new position. As you can see from the menu at left, you can also click options to rotate the selection 90 or 180 degrees (with no mouse dragging).

 

As before, you must click the check mark on the options bar to commit to your transformation.