Teach it to someone else, even an imaginary student. If you can explain a concept simply and out loud, you understand it. If you stumble, you've found the gap you need to study. They call it the Feynman technique and it really works.

Go to your professor's office hours. Seriously. Almost nobody does, and the ones who do get better grades and better recommendation letters. Professors WANT to help students who show up and care. It's the most underused resource in college.

Don't pull all-nighters. The research is clear that sleep is when your brain actually consolidates what you learned. Studying until 3am and then taking a test exhausted is worse than studying less and sleeping. Trust me, I learned this the hard way.

I graduated college 5 years ago and wish I'd known this earlier: the specific knowledge you learn matters less than learning HOW to learn. Develop good study habits and critical thinking skills and you can adapt to any subject or career.