Instructions
Stay calm on the outside. You may not be able to control feeling angry or frustrated at the situation; however, don't allow yourself to say anything or react until you feel that the immediate negative feelings have subsided.
Save criticism until you're away from the other players. It may be impossible to completely resist complaining about your competitors. However, this should only be done to close confidants once the other players have left.
Congratulate your opponents. Offer to shake hands, and let the other person know that you appreciate playing him. This demonstrates friendliness and goodwill.
Don't give excuses for losing. This is seen as unsportsmanlike, and especially so if you criticize other people on your team.