(MONEY Magazine) – Your college countdown actually begins when your child becomes a high school freshman and embarks on the four-year course of study that eventually leads to college. This calendar, designed to be used primarily by your son or daughter, can help organize the college search. And it can even boost your child's chances of success -- by making sure he or she allots enough time to the various parts of the quest and doesn't overlook key deadlines. ''Failing to plan ahead will handicap you during the admissions process,'' warns Alan Haas, president of Educational Futures, a private counseling service in New Canaan, Conn.

FRESHMAN YEAR September: With the help of your parents and the guidance counselor at school, begin to design a four-year course of study that will prepare you for college. Keep in mind, for instance, that many highly selective schools require their applicants to have had two or three years of one or more foreign languages and at least three years of mathematics. ,

SOPHOMORE YEAR September: Update your course plan with your guidance counselor. You may, for example, want to sign up for courses that will prepare you for advanced- placement exams. High scores on these can give you college credits for material you learn in high school.

October: You might consider warming up for the big college entrance exams -- given to juniors and seniors -- by taking one of two practice tests. The Preliminary Scholastic Aptitude Test (PSAT), a scaled-down version of the SAT, assesses your math and verbal skills. The P-ACT+ is in part a rehearsal for the ACT Assessment, covering English, math, reading and scientific reasoning. The P-ACT+ also includes a questionnaire that is intended to help you figure out your academic and career interests. Neither test is required, and the results will not be forwarded to any colleges until after you've taken the SAT or the ACT.

JUNIOR YEAR September: Review your course of study with your guidance counselor. Register for the PSAT that will be given in October, even if you took it last year. Reason: juniors who get top scores on the PSAT can qualify to compete for one of 6,100 National Merit Scholarships of at least $2,000. Watch for college fairs at your high school or other nearby locations, where you can question representatives from a wide variety of colleges and pick up brochures and other descriptive materials from schools that interest you.

October: Take the PSAT. This year's scores won't go to colleges now -- unless you ask to have them sent. At best, you'll get into the running for a National Merit Scholarship; at worst, you'll be better prepared when you take the SAT.

December: The PSAT results arrive. Your scores, along with your grade point average, can give you a rough idea of how competitive a school you should aim for. Together with your parents, meet with your guidance counselor to discuss the types of colleges and universities that seem most suitable. Decide when you will take the SAT or the ACT; the exams are given several times a year, and you must register about six weeks in advance. (Check with colleges to find out which they prefer.) In most cases, you'll be better off taking the appropriate exam twice: in the spring of junior year and then again in the fall of senior year.

January to April: With help from your parents and guidance counselor, draw up a preliminary list of 15 to 20 schools. Gather information about them, & including their financial aid policies, in your high school's guidance office and from the colleges.

Spring vacation: This is a good time to make casual visits to different types of local colleges -- urban and rural, large and small, public and private. Question students about their likes and dislikes. You might even have an interview with an admissions officer or two -- just for practice.

June: This is one of the more popular times to take Achievement Tests -- given five times a year -- which measure your knowledge in particular subjects, such as U.S. history, a foreign language or a science. Most top colleges require at least the English and math tests. Consult directories of local scholarships at your guidance office.

Summer vacation: If you plan to tour campuses in August and September, make the appointments in early July. You may find it more convenient to travel in August, but it's better to visit colleges while classes are in session. Assemble a list of your activities, job experiences and interests; it will come in handy when you fill out applications. Begin to ponder common topics for application essays, such as a person or an experience that influenced you or an issue you care about.

SENIOR YEAR September: With your guidance counselor, develop a final list of about six schools. Draft application essays and submit them to a parent, counselor or teacher for comments and proofreading. Line up teachers to write recommendations for you. Make sure your transcript is accurate and up to date.

October: Early-decision and early-action candidates should finish their applications, usually due between Oct. 1 and Dec. 1. Parents should begin organizing the tax records they will need to fill out financial aid forms.

December: Your guidance office may require a list of the colleges you're applying to so that it can send out your transcripts in time to meet January application deadlines. Pick up financial aid forms from the counseling office and have your parents fill them out. Early-action and early-decision responses will begin to arrive in the mail.

January: Standard application deadlines commonly fall on these dates: Jan. 1, Jan. 15, Feb. 1, Feb. 15 and March 1. Make sure your high school guidance office sends transcripts of your first semester grades to the schools to which you've applied. File financial aid forms as soon as possible after Jan. 1.

March and April: As decision letters begin floating in, try to stay calm. If you are put on the waiting list by a favorite school, write to the dean of admissions expressing your eagerness to attend. Include any favorable news about yourself that you haven't already submitted, such as improved grades, and consider visiting the school. If you have been rejected across the board, resist the temptation to join the Foreign Legion: there's still time to find a spot. Ask your high school adviser or an independent college counselor to identify suitable schools that still have openings in their freshman classes for the coming year. When you find one that appeals to you, have the counselor call to confirm that there is a place for you and to tell the admissions office that you want it. You'll have to submit an application, but your chances of being accepted are very good.