This is your chance to express yourself, and let the schools get a sense of your personality. The general GRE is required for admission to most graduate programs. Some schools require an additional GRE Subject test. The subject tests are designed to gauge your knowledge of a certain topic. It lets you apply online to some of the best programs in the nation, checks for accuracy and completeness, and allows you to return to your application and make as many changes as necessary.
Most graduate students receive some form of financial aid.
The most common source of aid is loans, whether Federal or private. A number of institutions allow you to borrow money to finance your education. Almost all graduate programs offer their students financial aid in the form of assistantships and fellowships. These require that you to teach classes, assist with research, or perform other academic related services in exchange for tuition. Many of these programs also provide a salary.