If you want to become an actuary, you should never try to do the minimum amount of work needed just to pass. Actuaries are responsible for massive amounts of other people's money. It makes sense for actuarial examinations to have very high standards. Never cram for a test; when you take an actuarial exam and you read a problem, you should immediately know how to do it. The formulas should all be memorized; do hundreds of practice problems and review your list of formulas for memorization daily.
Take a course on insurance. If you're going to work in the insurance industry, it helps to know something about it. If you hate insurance, then you most likely won't enjoy being an actuary.
Most employers look for candidates that have had some actuarial experience before consideration. An internship is pretty much a requirement, so try to get one, or ideally two internships during your summer months. This will also help you decide if you're headed on the right career path. Employers also look for good computer skills, so the better they are, the more likely you will be considered for a position.