I hope nobody is thinking, "Writing a story is tough enough; why would I want to try and write it backwards?" And yet by the end of this, I hope you have an answer to this supposedly rhetorical question. In fact, some things are best written backwards. I am sure some authors would never admit to doing it, and others would just lump this in with the greater concept of revisions, but indeed it is done more often than one might think.
We all know the standard story structure - hero starts some kind of physical or emotional journey, overcomes obstacles, changes along the way then hopefully accomplishes goal. Easy stuff. We should know these components before we even start writing. That's the part we don't necessarily have to write with the backwards technique. However, we can start picking parts of this from end to beginning and discover what we will need to make this a full, rich, and entertaining journey.
Oh - let's not forget the part of the story called, "changes along the way." When we write that big final scene, we establish the final version of the character. This gives us a chance to ask ourselves just what changed. Did they discover a friend was an enemy, that they had been living a lie? We start making notes about these changes, because they all have to be incorporated into the story - as we write the previous scenes.
With our backwards technique, we can then start to write the supporting scenes - the discoveries, the conversations, all the parts where some element is revealed. At this point, it's a checklist of all the elements we have noted from the two sections we've already written. We build them scene by scene, filling out all of the important parts then ultimately creating a story.
Which leaves us with the introduction. At this point it's very easy, because we have already explored the hero's journey. We get to start off the story as we wish, already knowing what this character should be in the beginning. We have taken the hero at the end, stripped away all of the growth and revelation, and left us with the person ready to go on an adventure.
This may sounds fairly complicated and possibly convoluted, and it is a difficult process. However, most writers unknowingly use this technique when they edit their work. They look at the ending, examine what they've said, then try and see if everything written prior to that leads up to that point. Then they go back through their text and check off everything point-by-point, which often requires a few big re-writes.
I would never recommend this to anyone who wants to start off by writing the Great American Novel, but try it with a short story. Write the concluding 200 words, think about what needs to be said for them to be powerful, then write the previous 200 word batches and so on until you reach the beginning. See what happens - it might just surprise you.