I had had enough of ChatGPT sounding like a machine and repeating the same forms.
So I forced it into rehab: no em dashes, no buzzwords, no “in conclusion.” Sentences short. Advise directly.
I keep my rulebook under 1500 characters (Custom Instructions limit).
Set it: profile icon → Settings → Personalization → Custom Instructions.
Sharing my prompt in the comments if you want to try it.