For my own original adventures, I develop a plot hook, think about a few locations I might want to run them through, so I can steer things if need be. I work out some villains to challenge them and stat them out as far as needed for the system. I try and make the plot hook something that will interest the characters' motivations, sometimes focusing on a single player for that session or arc.
Then comes the hard part, I rely completely on the players to direct where they want to go after they bite the hook.
I'm pretty good at thinking on my feet and stitching things together, sometimes to my own shock. If they want to investigate a specific clue, I'll give them some options and let them pick, then I'll have to work up the relevant NPC on the fly, complete with quirks and accents. Sometimes they become favorites and I get to reuse them, like Benedict Fawkes, the sleezy magician I heavily based on Matt Berry's Lazlo Cravensworth character on #whatwedointheshadows
It's exhilarating DMing by the seat of your pants. I live for the chaos.
#GMLife
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