Enlightened DMing is to simply set up all the pieces of the BBEG’s plan on the world stage in your head or documents, and throw the players at it. Obviously, ensure that the plan is something the players have enough tools and resources to overcome, and prepare for what their decisions will likely guide them towards in the next session, but…
Any old video game can run you through a story. Few video games give players choices. And no video game can be truly derailed.
Understanding that getting derailed is arguably the entire point of DnD, is DM Ascension.