As generative AI becomes an increasingly familiar part of higher education, the most important question may no longer be whether students should use AI at all. A more useful question is when AI should enter the learning process. By delaying AI, educators may be protecting a period of productive cognitive struggle before technology begins shaping students' thinking. As students encounter AI beyond carefully designed classroom activities, they will increasingly need to regulate their own use of these tools. This means developing practical habits of good AI use: generating ideas before prompting, critically evaluating AI suggestions, and using AI to extend rather than replace their own thinking.