Rock paper scissors cannot be properly played in this fashion. It is, ultimately, a game of psychology after all. You have to look you're opponent in the eye, figure out how many levels he will go to in calculating your probable move, and then take it one step further.
Only half kidding though. Next time you play, tell you're opponent, "I'm going to choose the rock."
They think "ok, well he either is really going to choose rock, and just trying to psyche me out, so I could choose paper. Or, he wants me to think that that's what he's doing, so he can choose scissors when I go to beat his rock with my paper. Hence, I should choose rock to beat his scissors."
See, by telling them you're choosing the rock, you kind of steer them towards this line of thinking where it is unlikely that they will choose scissors. They think its a 50:50 choice, you're full of it, and expect them to know it, or your telling the truth to psyche them out. So you then choose paper, and the worst that can happen is a draw. Obviously doesn't always work, but in my experience, it really does seem to increase your chances of winning.
