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The loser of the winner's bracket plays against the winner of the loser's bracket, and then the winner of that match plays against the winner of the winner's bracket. It's entirely possible for the same two people to play both matches.

http://www.printyourbrackets.com/32teamdoubleelimination.html

here's a pretty good illustration of how one works, though it doesn't have the names filled in.

I didn't understand that bracket :/ but it's ok I'll go with the flow thanks!

Basically, it's split into two parts, the upper and the lower bracket. Everyone starts in the upper bracket until they lose a match. Each round, those who have not lost yet remain in the upper bracket and play one another. In the lower bracket, matches each round are comprised of a pool of people, half of whom have lost one match prior and half of whom just dropped down from the upper bracket.