Fighting techniques, and techniques of any sport where you face an opponent, require an external focus of attention, i.e., on the opponent and the environment. While learning fighting techniques initially you may have an internal focus, i.e., on how you move and what you feel, but when fighting, the opponent is outside of you–so as soon as you can do techniques correctly, you should focus externally, on your opponent, not on yourself.

An example of internal focus:

Apart from the internal focus in this demo, I also don’t like the short grip–which is great for twirling but not for power with accuracy at a long distance.

In a demo below the focus is external because the demonstrator is an experienced street fighter. Even though he doesn’t always look directly at the imaginary target, his focus is constantly on it and he has it in his peripheral vision.

An example of external focus:

The demonstrator still doesn’t take the advantage of the nunchaku’s full mechanical potential, he grips it too short, but being a competent fighter he has skills to fall back on.

More info on on nunchaku as a weapon, not a twirling toy, is in Self-Defense Tip #84 — Using Flexible Weapons: Nunchaku.

For more info on directing your focus of attention see Gold Medal Mental Workout for Combat Sports: A Step-by-Step Program of Mental Exercises to Make You a Winner Every Time.