Yu can create an illusion about yourself, making you appear any way you like. False Images does not make you any harder to see, and the size of the image must be at least roughly similar to your own (+/- 30%). It is both a mental illusion and an actual image, so it cannot normally be detected by touch.
Using False Images takes a roll of Powers against a difficulty of 18. If the Outcome is negative, this is the number of shots that your Image is in flux until the new Image takes. Only if the roll is lower than the Charisma of whatever you are changing into will it fail.
Whenever someone viewing the False Image has a good reason to be suspicious of it, that person may roll Magic vs. your Powers. If this succeeds, the character gets a strong feeling that the Image is false, and a rough feeling (based on the Outcome) of what you really look like. Special powers, thorough examination, or close proximity can allow other abilities to be used. Powers, Sorcery, Deceit, Investigation, Seduction, and Medicine may all be possible under the right circumstances.