Have you ever daydreamed about playing golf while you are awake? When that happens your brain makes connections between the images in your head and the muscles that control those movements. It is like taking mental reps. The most effective visualization techniques should include as many senses as possible. To make the most of your mental reps you should see it, feel it, and hear it.
The use of three senses helps make the visualization more realistic and memorable and allows you to have an entire movie in your head.
The best time to visualize is right before bed. Your mind tends to replay those images at night. When you lie down to sleep, play all 18 holes in your head. Use all your senses; take your time. See yourself hitting good shots. See yourself reacting and recovering from bad shots. Dedicate 20 minutes to this process. Increase your mental reps!