How?

Change our expectations.

You will without a doubt hit some bad shots during the course of your round.  You should, he best players in the world do.  The trick is to learn to dismiss them as soon as they happen and move on.  If you go into a round of golf knowing that at some stage you will hit some poor shots then when they do occur you are not so taken aback that you follow the poor shot up with a dumb shot.

You cannot change the shot or the outcome so the sooner you accept the shot and move on the less likely you will worry about it, let it bring you down, affect your confidence and create tentative play within your whole game.