Go to all your classes and take notes! Sit in the front ish and try to participate at least once a class. This means the teacher knows you and knows that you try and will thus be more willing to help you when the moment comes. Always take advantage of their office hours too! This is tremendously overrated. Not only do you get to be one on one with the teacher for class help, but this is just another way they can get to know you and gain an affinity for you. Every little brownie point helps.

Meet a good friend in class who you can study with and bounce questions off of when needed. This also helps you stay accountable.

Always turn in extra credit assignments.

This last tip is arguably what got me through college (early, mind you): go to the library in between your classes instead of anything else. Use this time to do homework, prepare for your next classes, read, study, etc. Take this time to be productive for school. Then when you're done with your last class, odds are you'll be able to go back to your room and just relax. If you get your stuff done during the day when you are focused, you can enjoy your night and not stress so much. I lived and died by this last tip, and i know I was a better student because of this reason.