One of the major differences between great climbers and good climbers is their ability to visualise a route. Good climbers visualise from a third person angle, watching themselves as if they were looking through a camera. Great climbers visualise from a first person angle looking at each move through their own eyes.
Try and visualise yourself climbing a route. Now try and visualise each move as though you can see your hand moving towards a hold, your foot reaching for each foothold.
Can you see the difference?
By visualising in first person mode you are preparing yourself for what the route will actually look like when you get on it.
Next time you are stood at the bottom of a route and doing your route read try to visualise yourself climbing it.