Practice using the parallel, or straight-ahead viewing method
Can you make a pig in the middle by aiming your eyes far away? Is the little circle under the middle pig further away from you than the bigger circle on the outside? If the little circle appears closer to you than bigger outside circle, you are crossing your eyes to fuse. Look away and try again. If you're having trouble, try this trick: lean forward and place your nose on the screen, and then slowly pull backwards, keeping the third pig in the middle. Now is the center circle further from you than the outside circle? Do your eyes feel relaxed?
Can you aim your eyes straight ahead and make one cat in the middle that has both a bow and a tail? If you're doing it right, the little circle below the middle cat will look further away from you than the bigger outside circle. (If the little circle in the middle looks closer to you, then you're using the cross-eyed view method. Try again!)
Use the straight-ahead viewing method (the far-away look) and see if you can make a third Superman in the middle of the other two. If you do it right the little circle in the middle below Superman should be further away from you than the bigger circle on the outside. Also, the "S" on Superman's chest and his head should appear closer to you, while his arms and feet should look further away. If you can do this, then consider yourself a Vision Superhero!
Try the straight ahead viewing method on the spider! The little circle below should be further away from you, and the spider's head, back, and a couple of legs should look closer to you