The uptight dudes that HAVE to win every game are the ones who get diarrhea before games... and end up making embarrassing, random mistakes (like own-goals).
While my approach didn't, doesn't, and will NEVER mean a high win percentile... the "confidence" instilled from it is not being afraid to lose a match.
On the upswing of it the no-fear, all-fun approach usually DOES mean you make a spectacular play done out of risk that the audience gasps at.
IDK if winning is the most important thing to you my approach is useless.
Don't compare yourself to others!!! You can only be your best (I know that sounds really cleshay). Unless you know your better than someone than you can compare for a confidence boost. I don't know what your position is but if your a forward and you mess up don't worry you've got mids behind you, midfielders don't worry defenders are behind you, defenders there's a goalie and goalies the forwards never should've lost the ball so don't worry about it!
Good luck!
Dont tug shirts or flop
If you want to avoid flopping in any sort, type in Robben Flops
Practice more, if you are good enough, you will be more confident.
http://www.goaloo.com/1.shtml