Even if you don't know what your intended major is, just take some classess. Every class gives you opportunity to grow and learn and to hone in on what it is that actually makes your heartbeat. Its o.k. to not have all the answers right out of high school. I would also recommend finding a way to pay for the majority of your education (or be successful in winning scholarships). The last thing one wants, is to be heavily in debt when they are beginnning their career.
Learn to make better use of my time.