Acknowledge the existence of emotion and its impact upon your decisions. Think of a recent decision, or an act, that was controlled entirely by emotion. A situation in which you became angry is an example of emotional behavior. Think about what you would have done differently had you been acting entirely rationally.
Accept the fact that your emotions will always have an impact on your rationality. You will not succeed in completely blocking emotion from your mind and must acknowledge that fact. You can then identify emotional responses when they occur and understand how they are affecting your behavior.
Understand that you can control your thoughts. Remain calm when emotional thoughts enter your mind, examine them and understand why they are there. Then, allow them to leave your mind.
Separate your emotional responses from your rational ones and allow your rational mind to dominate the decision-making process. Take as much time as you can before responding to any situation. This allows you to respond in a calm and controlled manner.
Regularly explore your mind to discover what situations cause emotion to override rational thought. Understand that you are entirely in control of these emotions and can ensure that rational thought is dominant.