Almost all attacks are preceded by an indicator, or several. You must identify the pre-attack indicators as part of your situational awareness. Here are some common ones:
Verbal Threat – Yes, if they are talking, they are not attacking; however, this is certainly a pre-attack indicator. Telling you that they are going to beat you should certainly rise to the level of a personal threat and you should prepare yourself.
Scanning – Is the individual approaching you looking directly at you, or is he looking around to see if others are watching him? Is he looking for witnesses, the police or an escape route? The important question is, why is he not looking at you?
The Target Glance – Is the potential attacker preoccupied with a particular area of your body? Is he staring or repeatedly glancing at an intended target area to strike? Possible target areas are your eyes, throat, chin or nose. Do not forget that some additional target areas might be your hips or upper legs. The attacker might be preparing to take you down to the ground with a tackle.
Clenching – You should look for both clenching of the hands or the teeth. The constriction of either of these areas indicates physical stress and the possibility of an imminent attack.
Eye Blinks – The average eye contact between friends and others are about three seconds. One of the most common things you will hear about potential attackers is “the thousand yard stare”. When a person looks through you versus looking at you, there is certainly a potential problem.
Fighting stance – Taking a fighting stance is an obvious precursor to a fight. If the potential attacker places one side of his body behind the other and his hands come up, the likelihood of an attack has certainly risen!
Flanking – This is normally associated with multiple opponents. If you are facing multiple threats and they begin moving around to gain a better position, they are probably cutting off your avenues of retreat or escape. Do not allow yourself to be flanked.
There are many more pre-attack indicators. I highly recommend you read and conduct your own research. Pre-attack indicators are the key to writing an effective statement for the police especially if you have used force to defend yourself.