With the imminent release of Star Wars: The Force Awakens, you might want to refresh your memory by watching the earlier Star Wars films, or even the films and other related productions.
There are two or three philosophies on this. The most obvious is to watch the films in chronological order, or story order, so you are seeing the historical development of the things that happened. This is simple. Watch Episode I first, and work your way in order through Episode VI.
There are objections to this method, however, because the way the story was told, out of historical sequence, involves…