You can also apply for government grants, which are free sources of money offered by the government that you can use to pay for school expense. The best thing about them is that you don't have to pay them back. In order to be eligible for a grant you need to complete the FAFSA (which you also need to complete to be eligible for federal student loans). You can complete the FAFSA here: http://www.fafsa.ed.gov/
If you can not get any free financial aid, then you can apply for federal student loans. Federal loans are better than private loans because they have lower interest rates, and the government will often pay the interest for you as long as you stay enrolled in school. The two best types of federal loans to get are: