We've almost reached the knockout stage, which means we've almost reached our first World Cup match decided by a shootout. And every bozo from your local pub to M.I.T. wants to tell you their unbeatable "secret" to penalty kicks. Hooray.
So what is the secret? Happiness, of course! Researchers at the University of Groningen (yeah, right!) have deduced that the key to winning a penalty shootout is to "convincingly celebrate" your success with teammates. That's it. By studying the reactions of players who scored a goal when a shootout was still tied, they determined that players who clearly expressed happiness and pride—an actual example they seriously gave: "throwing their arms up into the air"—were generally on the team that eventually won. They believe it demoralizes the enemy, while passing your "contagious" positive attitude on to teammates who still have kicks to make.
Seriously, all you have to do is be excited. Why didn't I think of that? But what do you do if you miss? Probably lose, because you kinda needed that goal.
So Step 1 is to raise your arms ... but not too much, because that might give away the direction of your kick to the goalie. Eggheads at Rensselaer Polytechnic Institute (enough with the fictional university names, already!) claim there are at least five reliable indicators that kickers display that can reveal the direction the ball will travel before they boot it. Joint and foot angles as well as "distributed movements" throughout the body could give away your intentions without you even realizing it. So I guess you should try to find some way to put the ball in the net without kicking it and that will greatly increase your odds.
The question is—does your overt happiness outweigh the keeper's ability to read your mind? What if your happiness is one of the indicators that actually makes it easier for him? Quite the conundrum, isn't it? I would just stick with the most tried and true strategy of all: Kick it right at the goalie's nuts. Never fails.
Winning a soccer penalty shootout: cheering convincingly increases changes of success [Science Daily]
Left or right? Early clues to soccer penalty kicks revealed at Rensselaer Polytechnic Institute [Eureak Alert]
See also: England's Greatest Fear: A Penalty Kick [Bentern]