Put a weapon in the items slot just above your health by dragging it from your pack (put it in slot 1 for now). While attacking, just click on a target nearby, and when you swing all the way through--just after you do damage--just press the 1 key and quickly click on your target again. Repeat. It eliminates all of the recovery after a swing or shot. When you get really good at it your can attack up to four times in the time of one normal attack.