You can copy the appearance, powers, skills, memory, and personal equipment (any equipment they had on their person when you saw them) of any person you see (for a very broad definition of person). The target must be in your field of vision long enough for you to see them and you need to concentrate on copying them.
You can have an unlimited number of templates stored but can only use one at a time. While taking on a form, you remain yourself and are not mentally influenced by the transformation unless you allow it.
You can copy the powers of a target with Trumped the Trump in all cases.