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OK, here is where we have to watch those obsessive/compulsive tendencies...
but first, open your tile in MS Paint, drag on the page handle (lower right corner) and make yourself a good size page.  Select a smaller square from within your tile, hold down the Ctrl key, and drag a copy off to the side (1).  Still holding the Ctrl key, release the mouse button then click again and drag off another copy. 

While the second copy is still selected, go to Image/Flip-Rotate, select "Flip horizontal" and OK.  Your selected copy is now a mirror image of the first (2). 

Flip & rotate illustrated.

(3) Join the two images and you have a new tile, this one being symetrical and much classier than the original.

I usually make another copy of the tile and dragging/pasting copies, pile them up three or four high and wide, experimenting to see if I really like the patterns.  If I don't, I select a different part and copy-flip-join until I see True Beauty.  The problems come because of the infinite possibilities.   One begins to see more and more cool shapes as one makes more and more changes and adjustments, and soon one begins to loose more and more of one's self in the tile vortex (or something). 

Some uptight individuals are going to be crying about how all this has no socially redeeming value, but where else could you feed a faded politician or former world leader into the hopper and get a work of art out the other end? 

Take Bob Dole for instance...

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