The best way to prepare right now is concentrate on getting your graduation requirements done and enjoying your third year. The bar review course will start about two weeks after you graduate, and that's more than enough time to start really preparing for the bar, as long as you have your study plan in place before you start. The course, unlike law school, will guide you as to exactly what you need to study. They want to know if you know the way things are done in the state you're seeking to be barred in, and you slant your answers accordingly. You must of course know the law cold, have a consistent study schedule with time out for some relaxation and the inevitable emergency, and have a support system to help you keep your confidence up when the dark days when you think you can't do it come around.
Fear is the biggest hindrance.
The bar exam is billed as this dark and scary monster, and the bar examiners let you think that way. Don't worry about the passage rates - there are plenty of people who pass on the first try, and there's no reason you can't too. Just don't give the exam more credit than it's due before it's time for you to focus exclusively on it. But when it IS time to study for the exam, that's what you do, first and foremost. Give equal time to both your essay writing and multistate skills, and don't procrastinate on the subjects that you feel least comfortable with, hoping you'll get them by osmosis or something.