Too often writers will pad the manuscript. Add a sentence to each paragraph, or substitute filler that doesn’t bring anything to the story.
It’s not the best course of action to take, in my opinion because filler is, well, filler. There’s no substance to it. So it makes navigating through book a lot like crossing a bridge that doesn’t have any support. The middle sags and the whole of it becomes a lot weaker.
There is a way to add 20,000 words and strengthen the whole, and again, in my opinion, it’s a much wiser course of action for the writer to take because it best serves the story.
Add a subplot that echoes or mirrors the main plot.
Adding a subplot in this manner relates. It provides a vehicle to reinforce, show the opposing side, to generate deeper-seated conflict. It gives the writer a way to add additional layers to the conflict, which doesn’t diminish suspense and wreck pacing but strengthens it. A subplot that echoes the conflict in the main plot or serves as a mirror to it is adding support beams on the bridge.
How to do it:
1. Develop an arc for the subplot. Give it four or five steps, or scenes. Be sure the conflict in the subplot, the stakes and risks and obstacles, escalate as you follow the arc.
2.Now look at the existing manuscript for places that serve as a natural fit in the story line to plant those new scenes. Remember that the conflicts in a subplot resolve before the conflicts in the main conflict. And often the subplot’s resolution further complicates the main conflict or increases the doubt about the character achieving a “satisfying” resolution.
3. Go into the scene preceding each planted scene and insert transitions to the new scene by referencing the new scene’s POV character and/or the conflict.
4. In the new scenes you planted, insert transitions that lead naturally to the next existing scene in the story.
5. Double-check for inconsistencies in time, dates, and revelations.
6. Adjust as necessary, and you’re done!
Hope this helps!