Just make a Superman movie, then a Batman movie, then a Wonder Woman movie and then tie them all together in the Justice League movie bringing back Green Lantern and introducing The Flash.
It's not even difficult.
Why should they copy Marvel? Nearly everybody knows Superman and Batman foregoing the need for introductory movies.
Wonder Woman i'll give you that, Green Lantern had his already (as mediocre as it was) so i'd go a different way if only to separate myself from Marvel.
About the only thing i'd imagine that would work is building up the villain through several, hero centric, movies culminating in the big JL movie.
Let's wait and see what Nolan does with it.