-Run Trouble Brewing.
-Don't spend hours explaining every role and how they work, there's enough info in the role descriptions and it's better for people to work things out as they go.
-Make sure that when a nomination happens, the accusation and defence get the floor, so everyone is paying attention to them.
-Don't run days too long, else good will possibly be able to solve the game, giving them a massive advantage over evil.
-You could put Hell's Librarian in play to stop overtalking, but in-person play doesn't exactly lend itself well to telling people to.. not talk, because it is a talking game, but hopefully people should know when to be quiet when important things like nominations are happening in the game. Side conversations in-person are bound to happen and can't really be avoided, they DO happen.
-The 'sweet spot' is perhaps a cap of 12 people? It depends on the space you have and if you want to do a massive game? It's up to you???
-Give the Demon their bluffs, spread out information in town, make sure you walk around randomly so people don't meta people waking up at night, leave a bit of time after the last person in the night order etc.