I’m a huuuge fan of the Pomodoro technique. As a college student, it really helps me prune out the most productivity out of me.
It is tough in the beginning, so I used to start with 20-25 min sessions, but now, I can easily go up to 45 min sessions.
Definitely recommend Cal Newport’s blog posts on this such as this one: Deep Habits: The Importance of Planning Every Minute of Your Work Day - Cal Newport