I realize that this bet is for people who can almost have accurate predictions so they can win the bet. And for people who cannot predict or if you don't have good skills, then I suggest you be careful. I feel that I cannot predict correctly, and sometimes, I miss something in my analyzing, so I think it's difficult for me to predict where the price will move. But I am curious to see the result, and I wonder who will be the winner.
So, technically one must learned about technical analysis for a better chance of winning against other person whether the price will go up or down. You are correct that any person that doesn't have skills in predicting (only thinking randomly) are more likely to lose the bet but if the person you are against also don't know some skills then it would be harder to know which one will win and a little bit thrill.