Extend one arm straight out in front of you, with the thumb pointing toward the ceiling.
In the air, smoothly and slowly trace the shape of a large figure 8 on its side.
As you draw the 8, focus your eyes on your thumb, keeping your head upright, facing forward and moving only slightly.
Start tracing your 8 by beginning at eye level.
Move your arm up and over to the left, around and back to centre, then to the right.
Do three full 8s with one hand, then three with the other and finally three with both hands clasped together.
This integrates both visual fields, improving balance and co-ordination. Many people report better vision after this exercise.