Play with the puzzle first with both eyes uncovered until the child is familiar with the puzzle. When the pictures are easy to recognize, introduce the game of covering one eye at a time. You may use a scarf or a pirate's patch to cover an eye. The child may want you to use the patch too! A non-threatening eye cover is a cap pulled over one eye. Sometimes the child will allow covering of one eye but does not accept the covering of the other eye. In such a case it is likely that there is a difference in the visual function of the two eyes. Report your finding to your eye specialist.

If the child accepts covering of the eyes in turn, play with the puzzle and other favourite playthings with each eye separately, while the other eye is covered. When the child masters this play situation he is ready to be tested by the family doctor, your health care nurse or your eye care specialist.