Actually, my advice would be quite different from "work smart", though there are aspects of that also.
Get enough sleep. Every day. If you have exams, don't "cram" for them or stay up too late. Make sure you work steadily enough so that cramming isn't necessary and a brief review of essentials is all that is required. Just review your notes (and summaries).
Get enough exercise. Every day. Part of it is aerobic if possible, though just walking can also be a benefit. The time it takes for this isn't "wasted" as it lets your mind integrate the things you are learning.
Eat healthy and on a regular schedule. Avoid high caffeine and high sugar snacks. Or, limit them, at least. Avoid fad diets for balanced diets with fruit and veggies included.
Engage socially with people, face to face. At least a bit. Don't close yourself off.
Generally, watch your health and deal promptly with any issues. Don't neglect mental health.
As for the "work smart" part:
Take a lot of notes. Summarize those notes. Paper is known to be better than electronic (yes, there is research) as it engages your mind more completely.
Do a lot of reinforcement, such as by doing a lot exercises in your courses. Get a lot of feedback on what you do and what you write. Strongly prefer working on exercises over looking at solutions.
Ask for help when you need it, but try to answer your own questions first so you can respond intelligently to "What have you tried?".
Don't let social media dominate your life. Step away from the keyboard.
Have a schedule for work and play. It can be flexible, but stick to it unless there is a sufficient reason to deviate.