Using your head as a weapon is one of the most effective ways to protect yourself from an attacker
. The reason for this is that people don't expect a head butt from anyone. Most people think that a head butt hurts you just as much as an attacker, this statement is correct and wrong at the same time. Using your head incorrectly will lead to injury and you risk the damage of breaking your nose if done incorrectly.
When head butting a person it is important to remember never to lean back and tilt your head backwards and then lunge it forward in an attack. The reason for this is that an attacker can simply lower their heads and move onto your head butt, this will result in your nose making contact with the top of their head and this is a situation that is likely going to bruise or more than likely break your nose.
The correct way to head butt a person is to keep your head low and use the power from your hips and shoulders to thrust the top of your head into their face. Keep your head facing downwards at an angle and then thrust, if you connect with the person correctly you are either going to knock them straight out or you are going to break their nose or cheek bones. This method may appear violent and I completely agree, but you must remember this is a street fight and the other person may have far worse intentions that just harming you.
The head butt is such a useful self defence move because there is no technical knowledge needed, simply thrust your head in the correct way and it will do the rest for you.