The course should be set up so that the line is moving an even distance above the top of the grass - not dragging through it.
The line should not touch high points on the ground, or other obstacles that may be in the path of the line, like the edge of a sidewalk; landscaping logs; bricks, etc.
Once you get the course plotted out and string the line - if the line is touching anything other than the pulley wheel - reposition the pulleys and drive. If the line is coming into our exiting the pulley at an angle so that the line is touching any part of the pulley other than the wheel - it will cut into the pulley. It must only touch the pulley wheel for proper functioning.
Raise the pulleys by placing something under them - until the line is moving an equal distance (about an inch) ABOVE the grass/ground/obstacles and is entering and exiting the pulleys - wrapping straight around the pulley and not being pulled either up or down and must never touch any other part of the pulley.