The first step that one will take after deciding to pursue a career in the military is taking the Armed Service Vocational Aptitude Battery test. This is more commonly referred to as the ASVAB. The ASVAB not only determines whether or not a candidate is qualified to serve in the armed forces but also shows which specific job they have the most aptitude for.
AFQT scores are grouped into five main categories based on the percentile score ranges. Categories III and IV are divided into subgroups because the services sometimes use this chart for internal tracking purposes, enlistment limits, and enlistment incentives. Based on your scores, the military decides how trainable you may be to perform jobs in the service.
Many high schools give students the opportunity to take the ASVAB as part of career exploration. If you chose not to take one in high school, then you will have to schedule a time to take it. You can contact the Armed Forces Recruiting Officer in your area and you can schedule an appointment with a local recruiter from the branch of the military you wish to join.
[1] See two documents: Sims, W.H. and Truss, A.R., A Reexamination of the Normalization of Armed Services Vocational Aptitude Battery (ASVAB) Forms 6, 7, 6E, and 7E (Alexandria, VA: Center for Naval Analyses, September 1980); and Laurence, J.H. and Ramsberger, P.F., Low-Aptitude Men in the Military: Who Profits, Who Pays? (New York: Praeger, 1991).  

You’ll need to bring valid identification (photo ID, SSN card) to be admitted into the ASVAB testing room. Arrive on time— you’ll be turned away and required to reschedule if you are late. Your recruiter may give you a ride to and from the session, but he/she is not permitted in the testing room. You will not need to bring a calculator for the test.
Having military intelligence representatives participate in the execution of the national defence policy is important, because it becomes the first respondent and commentator on the policy expected strategic goal, compared to the realities of identified threats. When the intelligence reporting is compared to the policy, it becomes possible for the national leadership to consider allocating resources over and above the officers and their subordinates military pay, and the expense of maintaining military facilities and military support services for them.

Extra back-to-basics practice that has helped thousands of recruits to qualify for the armed forces. Thousands of military recruits need extra help to pass the ASVAB, or Armed Forces Test and here’s where they can find it! ARCO’s ASVAB Basics offers intensive practice in reading, vocabulary, and mathematics the subjects covered in the four ASVAB subtests that determine whether a recruit qualifies for enlistment. Now updated, it features: * Full-length ASVAB subtests for practice * Drills to improve basic academic skills * Complete explanatory answers.
Figure 2.7 shows FY 1977 as the low point and FY 1992 as the high point in accessing recruits in Categories I to IIIA. In FY 1977, 34 percent of accessions scored in the top half of the AFQT distribution. Only 13 percent of Blacks, 19 percent of Hispanics, and 20 percent of "Others" scored in Categories I–IIIA. [3] Fifteen years later, in FY 1992, the majority of minority accessions achieved scores in the I–IIIA range (Blacks - 56 percent, Hispanics - 67 percent, "Others" - 67 percent). Hispanics have shown the most marked increase, with a 48-percentage-point gain in Category I to IIIA accessions from FY 1977 to FY 1992.
Military history has a number of facets. One main facet is to learn from past accomplishments and mistakes, so as to more effectively wage war in the future. Another is to create a sense of military tradition, which is used to create cohesive military forces. Still, another may be to learn to prevent wars more effectively. Human knowledge about the military is largely based on both recorded and oral history of military conflicts (war), their participating armies and navies and, more recently, air forces.
Test scores provide only one measure of your skills and abilities.  Test scores and grades, combined with information about your interests, values, skills, and achievements may help you select appropriate occupations for career exploration.  As you explore careers, you can compare your skills with the skill requirements of occupations in which you are interested.