How? Well, one advanced technique consists of reminding the other player of the rules before the match starts, making sure to repeatedly flash them with the throw you want them to use -- for example, show them the scissors every time you say the word "scissors," but not the other ones, as you go over the rules. As long as you don't make it too obvious, their subconscious should take your suggestion and they will open with the move you commanded them to use.
Now that you have this knowledge, kindly avoid using it for evil.
Here's another cheat: Make it really obvious that you're going to throw paper next, and then throw paper. Subconsciously, your opponent will stay away from the move that beats paper (or whatever throw you were telegraphing) because they'll think that no one could be that obvious.
Yes, friends, with these techniques, you will always get to ride shotgun.
It's a view worth dominating the minds of your loved ones for.