When one starts to talk about golf sport psychology and particularly visualisation, then Jack Nicklaus has to be the best role model. Before selecting his club for an approach to any given shot, he would run a short movie of how he wanted it to look.
Before each and every shot he would preview exactly how the ball would fly or roll, how it would turn, and where it would come to rest. He would often picture himself out where the ball would eventually come to rest to get a better aspect of the shot.
Only after he had run this movie in his head would he select his club and step up to perform his magic.
I try to incorporate imagery into my training schedule and this prepares me for using it on the course. I also find that just before I go to sleep is a good time to visualise a swing improvement or even simpler, seeing your shot with a better ball flight. This helps as you are in a relaxed and tranquil state.
It helps to create an all-sensory experience that is as vivid and clear as possible. Initially, practising in a quiet environment can help to minimise distractions and facilitate clear images. See the flight, hear the swoosh or impact, feel the soft grip, and taste the success.
Visualisation makes big demands on your attention, so short frequent quality practice sessions are preferable to long ones. On the course these images will be short snippets which take mere seconds to construct.
Be careful as negative visuals always try to come to the fore. I personally keep mine simple and don't focus too much on the desired result.
Timothy Gallwey (The Inner Game of Golf) covers this well by suggesting that a super visual before putting is to imagine the task of picking the ball out of the hole before you make a putt.
Joseph McLaughlin (Zen in the Art of Golf) suggests that we should "see it done". See the ball lying in the middle of the fairway, green or hole and then track it back to your golf club and feel and visualise the swing you would have to make to achieve this.
In practicing golf sport psychology, in particular visualisation, the secret is creating vivid positive images and the best way to achieve this is through practice.
For example, close your eyes and imagine your are throwing a tennis ball against a wall. Imagine how your hand and arm perform this task. When you have a reasonable image, open your eyes and look at your hand and arm. Were your visuals good?
Do this until you become adept at it and you are well on your way to creating good visuals. Now do similar exercises with your other senses; imagining how the tennis ball feels when you squeeze it or the sound it makes as it hits the wall.
There are of course endless everyday examples and we can easily find five minutes everyday to improve these simple skills. These short sessions will help you to accomplish wonders on the course.