To avoid it becoming a 3 hour epic, you don't show the movie clip itself except briefly, and omit any scene you have no information on ... greatly shortening the amount of the actual movie people have to watch.
The main way to keep people's interest is to be funny. One of the funny things I was going to do in Jedi was play many of the stunts in slow motion to show people how everyone is obviously not actually hitting each other (Luke's action on the sail barge being ridiculous even in normal motion). I'm syncing Endor now and Han reacts to a punch on Endor before it hits, and then there's this jump cut as Chewie shoots a biker scout.
Terrible directing in the movie. Oh, and pointing out background aliens. The zoom function being your friend.