You point the wand at yourself and try to think of a good transformation. "Make me twins," you tell the wand. You feel like your body is being torn apart but curiously without pain, and then in front of you is standing an exact double of yourself.
"It worked!" you both say.
Fortunately, the clothes have duplicated too, but the wand hasn't. You're glad that you're the twin who ended up with the wand....
As you raise the wand your double says "Wait, that's my wand too!"
"Don't worry," you say. "I'm not going to do anything dangerous or harmful. But I'm glad this worked."
"Yeah," the other you replies. "We could keep using the wand on ourselves to test it until we decide to use it on someone else."
You nod and hold the wand up....