Popular since the last century stereo persist to this day.
It's really quite funny entertainment, despite the legend that not all people are able to see the image on the stereo image.
If you have eyes, everything will turn out.
Relax and take a comfortable position.
Zoom image close to the eyes.
Do not try to focus on the image, the eyes should be completely relaxed.
Start smoothly zoom out an image of the eye. The main thing - do not focus on it's eyes, otherwise all have to start again.
At a certain distance when the related parts of the picture "will overlap" each other, begin to form a three-dimensional image in front of you. Again, do not try to focus.
If the image is formed, but it did not manage to "catch", just move the eyes up and down.