I use it by pasting code into it and asking the LLM questions about it (e.g., what does this code do, what are other alternatives, why is this approach better, what are the tradeoffs, etc.). I keep asking it more questions whenever I don't understand something. I ask it to improve my code. It's not perfect but after using it awhile, you become accustomed to how to ask questions to get more useful answers and figuring out what kind of questions it can't answer.