You may need to establish that you intend to return to your home country after your studies are complete. You may need to demonstrate economic, personal, social, and cultural ties to your home country. Some of the methods of doing this include:
Likewise, if you have close relatives or financial interests in the USA, you may have difficulty getting a visa. If a consular officer believes that you intend to immigrate to the US, the officer must, as a matter of law, deny the visa.
You may be required by the INS to post a Departure Bond to guarantee your departure.