Put in the time and effort to do the work. In my opinion, that's the single most important factor in academic success. At least for me, getting really comfortable with the problem sets was 80% of what it took to get through the exams. Sometimes it's painful, sometime it takes way longer than you ever believed, but it will pay off in the end.
Staying organized to keep on top of that work is also key, and will probably save your sanity.
...but from personal experience, if you have any science classes (or finance for that matter), it really helps the learning curve a lot if you can stay a semester ahead of the math.
Other than that, sure orginization will certainly help, it's all about learning how to find the internal motivation, discipline and passion to get the work done and still enjoy the good times. Yet don't get so buried in the rote work to forget what your options and opportunities are.
You're smart, so in very short order, you'll be answering your own question better than anyone else could.
Reality is merely an illusion, albeit a very persistent one. - Albert Einstein
Your computer will crash if you try to do the report or paper the day before it is due because the computers have a critical need detector built into them so the more you need something the more it will crash and loose files. Hard to believe but theft is also a problem in college so don't expect a locked door to protect your stuff - engrave your name on everything and have digital photos of everything you own on a small CD or flash card and keep that safe. Try to do your homework right after class that covered the subject matter otherwise you will forget it - ask me how I know!