Literally. Studies have shown that human beings are almost twice as alert and also better able to concentrate on the task at hand when they walk with their chin held high regardless of how bad their last shot might have been.
Ignore golf between shots
When the wheels are falling off, you walk too fast, talk too fast, breathe too fast and play too fast. This, of course, means that you prepare for and hit each shot too fast and the cycle of bad shots continues. Between shots, shut down your golf brain talk about football, talk about the movie you saw the night before, talk about the weather. Anything but golf to clear your mind.
Create an "on-deck circle" for yourself
Like the on-deck circle in baseball, this is the place where you can think about your swing all you want. But the moment you leave the on-deck circle and step up to your ball that is, up to bat thinking stops and acting begins. At this point, you should have no more than one swing key in your mind, whether it's "rotate," "width," "extension" or anything else that keys your swing. Leave the rest of the jumble in your mind back in the on-deck circle.