How to always win at rock, paper and scissors

Imagine that you are being held at gun point the only escape is that you have to beat your assaulter at a game of the classic rock, paper and scissors. (Note this situation is a “bit” extreme but do bear with me!) If you only have one shot of winning the game there might just be sure-shot way of winning the game. The trick here is to make your would be murderer guilty or conscious about anything( I wonder what?). Keep in mind what you say to him should be…