This is one method that you can employ as you define all those reactions that come into your awareness. Basically, you are training yourself to be aware of your own tendencies. Do this in situations that you have a strong reaction to. To define these reactions by saying ‘how you feel’. Express them and then write them down in a record book or journal.
By defining these reactions, you are recognizing them and thus they (the thought patterns) become known or conscious to your conscious self. By expressing them, more and more of your karmic tendencies will be uncovered (and eventually be understood). This will continue until a time comes when the reactions lose their emotional charges. When they lose their emotional charges, you will be less interested in them. With that, you can consider this as having ‘cleared the karmic pattern’.