It is not possible to obtain a security clearance on one's own. The only way to get one is to have a current or perspective employer obtain one for you. Security clearances are costly and time-consuming, reports Monster Jobs.
Monster Jobs further reports that a security clearance is only provided by a company if deemed absolutely necessary. There are three levels of security clearance: confidential, secret and top secret. Applicants being considered for a security clearance have their fingerprints taken, complete a personal security questionnaire and undergo thorough background checks for issues, including any criminal record, history of substance abuse, personal conduct and any mental disorders. The clearing process may also include the use of polygraph tests.