Attend your classes, do your homework, get a job (to at least partially pay for school), join clubs, etc. And if you think you will be swamped, you very well may have certain weeks where you can't do too much because you have 3 or 4 tests. But trust me in the fact that you will have TONS of extra time on your hands. That is why it is crucial you join clubs and socialize with people.
Have a good attitude about how you will do on exams. It sounds stupid, but thinking you are going to do bad on an exam will likely make you do worse on the exam.
Try not to cram study. I myself do this on occasion, and it truly isn't enjoyable. Rather than cramming material in for 8 hours the day before a couple exams, study for 1 hour each day for the 8 days leading up to the exam. Not only will it not suck as much, but you will actually have a far better understanding of the material.
Feel free to go to parties and other social events with friends, but do NOT let it interfere with your schooling. Don't party if you have class the next day (Trust me, not a good idea), and if you are intending on partying on a Saturday night, think ahead. You are probably going to feel like absolute shit on Sunday, so it will probably be a good idea to finish all your homework on Saturday. That will leave you a full day Sunday to just chill.
Try to do your homework before gaming. I know it can be incredibly tempting to toss that homework down at times and start playing some games, but it is SO much less stressful if you finish your homework and then play the games knowing you are done for the night. You don't have to worry about not leaving yourself enough time, etc.
If you don't understand something, don't just give up. Ask somebody. Odds are, the teacher is more than willing to help you some if you have been doing your homework and attending class (if you don't do these things, many teachers will not help you, simply put). I don't know about your particular school, but for many generals at my school, there are completely free tutors available. Use them if necessary. Once you get to higher up classes, free tutoring will likely not be around, so don't be scared to form a study group or something of that sort to work through problems with somebody else.
Finally, the odds are likely you will get an occasional professor you simply do not get along with. Whether they just choose to hate you for no particular reason (I never have understood this one), or some other thing, it happens. Just continue trying your hardest, and if you wind up getting a C even though you feel you should have gotten an A or B, it really sucks, but you know you tried your hardest, and you know you learned something. Do not let this deter you from what you determine you want to do eventually.
I had a professor that followed this exact sample. The final exam was an essay based exam (for a finance class about investing...doesn't make much sense) that was for 100% of my grade. I get my final grade, and find out I got a D on the exam and got it curved up to a C due to doing well in the stock game that we played. I emailed him, only to receive a dickhead response saying 2 out of 5 of my essays were essentially horrendous, despite being exactly what the professor discussed throughout the semester. This kind of thing will happen to you. I just want to say again, don't let it get to you. Yes, it sucks that I got a C (when I try to be an A student), but 1 little C isn't going to ruin the rest of my life.
Money can't buy happiness. Just video games, which make me happy.
