Talk to your guidance counselor, if you're still in high school, about sending your transcripts to the various colleges. Your counselor helps you through the college application process and discusses your grades.
Locate the contact information of your previous high school, if it has been a long time since you attended. If the high school has a website, the contact information may be there as well.
Call the school, or check the school's website, to find out how to access your transcript records. If you still live near the high school, go in and talk to the administrative department to request your transcripts.
Produce your identification, pay any fees for ordering your records and give the address to the college admissions office. Follow up with the college to confirm receipt of your high school transcripts.