source: Universal NPC Roleplaying Template - The Alexandrian
Name:
Appearance: a boxed text description that you can use when the PCs meet the the NPC for the first time. Get it pithy. 1-2 sentences is the sweet spot. Three sentences is pretty much the maximum length you should use unless there is something truly and outrageously unusual about the character. Remember that you don’t need to describe every single thing about them: Pick out their most interesting and unique features and let your players’ imaginations paint in the rest.
Quote: a single sentence. You should be able to basically glance at it and grok the voice.
Roleplaying: Two or three brief bullet points at most. You’re looking to identify the essential elements which will “unlock” the character for you. include at least one simple, physical action that you can perform while playing the character at the table.
Background: essential context and interesting anecdotes. Is it something that will directly influence the decisions they make? Is it information that the PCs are likely to discover about them? Is it an interesting story that the NPC might tell about themselves or (better yet) use as context for explaining something?
Key Info: essential interaction or information that the PCs are supposed to get from the NPC, e.g. a mystery scenario in which the NPC has a clue. keep it organized for use on the fly
Stat Block: if relevant