There are six components to a good prompt: Task, Context, Exemplars, Persona, Format, and Tone. They have a specific order of importance. You don't need all six every time - but knowing which ones are mandatory, which are important, and which are nice-to-have changes how you write every prompt.
The order of importance
Mandatory: Task
Important: Context and Exemplars
Nice to have: Persona, Format, Tone
The mental checklist
Before sending any prompt, ask yourself: