Twirl wand around self, or tap other target.
Causes object or person to take on the appearance of what's behind it, like a chameleon.
The Disillusionment Charm (incantation unknown) is a spell that is used to conceal the target. The charm makes that which has been bewitched to act as a chameleon, taking the colour and texture of that which is behind and around them.
Casting and Effects
It is presumed that there are two methods of casting. It seems that if one is using the charm on themselves, they must twirl their wand around themselves as though they were wrapping themselves in rope. If, however, they are using it on an external target, they must merely tap on the target with their wand. This then produces a sensation that a raw egg has been cracked onto the person's head as the charm travels down them, granting them invisibility.