A person may watch his thoughts by becoming more aware of what happens to him emotionally when he is thinking. Many people find meditation helpful for doing this. Sitting quietly for a little while each day and focusing on the thoughts that pop up can be helpful for recognizing unhealthy thought patterns. Once these patterns are recognized, it becomes easier to change any negative effects they cause.
Another method of watching thoughts is hypnosis. Hypnosis is a way to become more aware of the thoughts happening in the subconscious mind. Hypnosis works by putting a person into a hyper-relaxed state in order to allow him to avoid all the mental clutter that often happens when he is going about his daily activities.
During the hyper-relaxed state of hypnosis, a person increases his ability to mentally receive positive, self-affirming messages, and he can more effectively absorb those messages into the subconscious. When he is back in an alert state, he is more likely to be able to control or avoid thoughts or actions that are not desirable. Hypnosis should always be performed by a health or medical professional who is experienced with the practice of hypnosis and with providing therapeutic services to patients.