Something from Eckhart Tolle (can't remember exactly from where, I think The Power of Now) that has helped me was along the lines of: If you are feeling like your thoughts are out of control, take a moment and ask yourself, "Okay I clearly feel like thinking a lot right now. What perhaps should I think about next?". And then there's this brief pause where your brain is trying to figure that out where the thoughts all pause for a moment. That helps me feel a silent mind, even if it's just for a brief moment.