Great golfers meditate. Some of them don't know that they're doing it but the best ones usually do. Call it golf psychology, call it hypnosis or the mental game of golf, its all the same thing - using your mind to improve your golfing results. You can use a golfing meditation whenever you have a spare few moments whether that's before or during your game. Take a couple of deep breaths let you body relax (actually imagine all the muscles relaxing) and clear your mind of all negative thoughts. This takes practice and is much more to do with letting it happen than making it happen. Then fill your mind with all your best golfing resources, all of your best shots, best feelings, strongest beliefs. And then, actually rehearse in your mind for your success, see yourself achieving it.
Practice this constantly, don't do it once and give up because it doesn't work that way. It's a habit not a gimmick. This habit will improve your golf.