Ghostwriting usually begins with the client rather than the writer.
You provide the ideas, experience or subject matter. The ghostwriter then turns that material into finished writing in a style that reflects how you naturally communicate.
The source material can come from conversations, interviews, rough notes, presentations, voice messages, existing articles or even a few bullet points.
The writer drafts the content, you review it and feedback is used to refine both the individual piece and the writer's understanding of your voice.
With an ongoing relationship, this normally becomes easier over time. The writer becomes familiar with the subjects you care about, the way you explain things and the language you would or would not naturally use.
The result should not feel as though somebody else has borrowed your name. It should feel like your ideas have been given the time and attention needed to put them into words.