what is the procedure for selecting wonders of The world?

I believe … for the New 7 wonders … it had to be man-made. Then a group of “experts” selected some sights, people from all over voted on it via telephone, and eventually the organization released their list of the seven new wonders of the world.

Set your criteria. Can it be seen from the moon?(The Great Wall of China) does it have a minimum age?(The Pyramids) Choose based on these criteria.