How to master ChatGPT
Seven specialist models, agentic power-ups, and a one-weekend training sprint
The public release of ChatGPT in late 2022 felt like a Big Bang, by mid-2025 we’re living in the sprawling galaxy it formed. Monthly active users have cleared 180 million, and the model roster has ballooned from one vanilla GPT-3.5 to a buffet of specialist brains - GPT-4o, GPT-4.5, o3, and whatever codenamed surprise is gestating in the lab.
Keeping pace is brutal. Yesterday’s “advanced” prompt can look prehistoric two releases later, and every capability drop - code interpreter, vision, GPTs, Projects, scheduled tasks - reshapes what best practice even means.
I’ve spent the past year road-testing prompts, fine-tuning custom GPTs, and stress-testing workflows for marketing ops, data analysis, product ideation, and plain-old knowledge work. What follows is the manual I wish I’d had on day one. Steal it all, then bend it to your use-case.