So, when you say writing, are you asking about the actual letter and word formation, or what we would probably call ‘composition’?
From what I have learned here, the CM method for handwriting and letter formation would be short periods of copywork executed very carefully to give the child the habit of doing the writing with excellence. At our house, we use a timer and the child carefully copies a selection for anywhere from 5 – 15 minutes, depending on their age and ability level. So, perfect (by that I mean, best effort) execution in copywork comes first.
Once the child is trained to make letters properly and to the best of his ability, he should begin to do copywork of beautiful and interesting sentences and ideas.
Next is oral narration, or the habit of listening and then telling back to you what was read.
Prepared dictation and eventually, written narrations would follow when the child is orally narrating with excellence.
That is kind of the ‘scope and sequence’ of the CM language arts as I understand it. SCM has a resource in their store called, “Hearing and Reading, Telling and Writing” which may help. Also, the all day seminar was a terrific resource for me when I was transitioning to pure CM principles in our homeschool.
Hope that helps! You might also search for a question I had about writing (compositions) a few days ago. There were loads of wonderful thoughts about writing on that thread! I think it is under “Writing – What do you do?”.