Another way is to buy a book that has the questions, and study that until you are comfortable. Then take a few practice tests as stated above, then go take the test. Look online for a local test session. Local clubs will be able to help you. Some may also offer classes. I used the books by Gordon West and recommend them highly. Every question is in the book, along with the possible answers, the correct answer, and an explanation with key words highlighted. The ARRL also has books.
I read the Technician book through twice and passed with 100%. Did the same with the General and passed with less than 100%.