Open the picture on which you'd like to do the effect. Let it be 800x600 pixels, or bigger, so that the following changes can be shown better. In the panoe Layers duplicate the background (right mouse click on the Background and from the other menu chose Duplicate Layer...) and name it like you want.
Then new layer make proportionally smaller by 25%, by doing the following: go to Edit>Transform> Scale... under the main menu you will see extra options for the transformation. In the spot W (for width ) put: 75%, in the H (for height ) put 75% and check by clicking Enter two times.
Now duplicate the new layer (the layer you just transformed) and just repeat the transformation (Edit>Transform>Again or the shourtcut on the keyboard: Ctrl+Shift+T). Repeat this 4 more times (don't forget to always duplicate a layer on which you just made the transformation).
If you succesfully finished the last step, connect all the layers: go to Layer>Flatten Image. Then go to Filter>Blur>Radial Blur. put in the meaning 25, for the method chose Zoom and Quality: Good, and then click OK.
The whole process can be reapeated with new transformations and angle of 15 deegres. On the end the whole picture should be rotated for 90 deegres (Image>Rotate Canvas>90º CCW)...
