Assuming that I know you and you were my friend, I'd have you tell me details about times we've shared together or conversations we've had--things that no one else would have insight into without having been there with us.
This would let me know that it was really "you" and not the person whose body you're in.
How would you respond if I..... told you I had a crush on you and asked you to recite poetry to me.
I'd be thoroughly disinterested, I struggle to derive pleasure from material things... then I'd go out and buy myself an Eleiko barbell and an entire set of calibrated powerlifting plates.
How would you respond if I gave you a lantern, but told you you should never rub it?