Librarians are on the cutting edge of information technology and are always involved in something new and exciting.
Graduate from high school.
Learn about librarianship from the American Library Association website. Also check out the federal government's Bureau of Labor Statistics Occupational Handbook Online. Investigate what library type you would like to specialize in. Choose your college major accordingly.
Graduate from college with a bachelor's degree in just about anything. Everything you learn is useful.
Choose a graduate school with a school of library and information science. The American Library Association website keeps a list. There are about fifty schools in the country. Some schools offer online courses. Graduate with an "MLS", Master of Library Science or similar degree title.
Do an internship or work part-time in a library while you're in library school so you can build up your resumé and learn more about different types of libraries.
Apply for a job and be glad you choose a fascinating, never a dull moment career with a high job satisfaction rate.
Learn management skills. A librarian is a manager first and foremost. You will have to manage people, budgets, leaking roofs, power hungry administrators and problem patrons. There is no "man behind the curtain" to run things, you're it.
Be prepared for people who want to stamp you with the "Marion the Librarian", dull and boring stereotype. These are usually people who aren't nice people to begin with and worse yet, don't read very often. Continue to be polite and professional, but open and friendly. This will help them get beyond the stereotype. Try to prove them wrong as much as possible. Show that as a librarian you can be fun and outgoing.