Understand that you can only control certain things and you can't always be perfect no matter how hard you try to be. Have fun because if you don't enjoy it there is little point in playing.
As golf is a game that has an almost infinate complexity, no one person will ever get everything about it and no one will hit it perfect everytime so it isn't productive to be anxious about where the ball goes and there is no need to beat yourself up everytime it happens - it is natural variance.