How about a sneak peek? Throw a hint at the what the ending looks like. A poem that speaks of the future may be the way to go. An essay about where you think things should go with a topic of extreme interest to you. A moment of foreshadowing for your character.

We are on the downhill stretch so why not shine a light on what is at the bottom.

However you see it, whatever comes to mind when you think sneak peek, go ahead and throw it in there.

Happy Writing!