Look into the centre (white point) and stare for a while. How many colours can you see altogether in the object? You should see a purplish circle... and the 4 rotating 'wings' are tinted green. Make sure you always keep focused on the centre.
Once you've done this, read on...

Are those four wings really green? Amazingly, they are exactly the same colour as the circle inside. Don't believe me? Well try following one of the wings round. You'll see that the colour matches the inner circle perfectly

Shift your gaze around this brilliant picture... You may see ghost discs glowing at the intersection points of the bars while clear bright spots pop up in their middle..

This is similar to the upside down illusion. just flip the picture and enjoy the Old couple changing position

Painting is not the easiest job to do but Donald Rust done some nice art work here. Spot the hidden lady in this picture

Some nice body painting to create a illusion. Well, those of you who’ve seen this kinda illusion before also will have no trouble understanding this one

What do you see? is that man really flying?

You might have seen lots of flower but nothing like this one

Check out the picture below which looks like a crocodile or a snake but the unusual thing about this picture is that it is painted on a hand.

An awareness test in the style of the selective attention / invisible gorilla test by Daniel Simons. Do the test. See for yourself. This visual attention experiment will test your awareness of what you see, and more importantly, what you miss.

There are various versions of this optical illusion -- including the monkey business illusion and the moonwalking bear. The video shows the fascinating psychology of perceptual blindness by our brains when we are strongly focused on something. During times of intense focus, our brains can miss even the most obvious images in full visual view, as this experiment shows. It's amazing how our brains can be tricked into "selective visual" blindness.

Take the test and see how the strength of your awareness measures up.

To create this kind of illusion you just need to make a good use of you sketch work and camera angel and you are done