What happened to Persephone?

So I'm sure you know about the Greek myth about the creation of the seasons. In all the books I have read so far about that myth, it says that Persephone took 6 or 7 pomegranate seeds (depending on the book) and ate it. Later it says that she has to return to the Underworld for 6-7 months because she ate the pomegranate seeds. But it never explains in detail about how it happens. I mean, does she get dragged back to the Underworld, or does she just "teleport" there? How does she get back to the Underworld???