They Line up with 3 central defenders, One defensive mid (Busquets) Then 3 mids as always, an attacking playmaker inesta, deep lying playmaker Xavi, and then a right midfielder in Dani Alvez. Then Fabregas plays through the middle as the false no.9. Messi is the trequista and has free reign on the right hand side, and then villa on the left hand side.
If you were to make the tactic, make it slow tempo, and short passing, high pressing. Make sure you get the messi role right!