How to prune a weeping mulberry so that it has main branches with lots of curves within its crown, as if they can't decide what direction to take, like this one: (look at wavy branches in the middle of the crown)
Or, take a look at this photo from http://plantwithme.com:
NOTE: The first two pics are from my neighbor's yard. He even wanted to be in the picture, I had the hardest time convincing him not to appear on photos.
When I said "pruning", I meant long-term pruning (20 year time span).