Recited from memory by Barbara, from her work with Thomas Richards, of the Social Anxiety Institute:
THOUGHT STOPPING AND DISTRACTING
First rule: Every time I have a negative thought, automatically say to myself "Stop! These thoughts aren't helpful. I choose to move in a different direction." And then do a distraction from your list of distractions (for 10 minutes: file, walk, anything to break the pattern, singing up beat songs...)
My commitment to doing this as a regular practice in my life.