+1 for Aviation Exam. When you start into the question banks, make sure you attempt the questions 'open book'. If you are not 100% sure of the answer, look up the correct answer rather than guessing at the wrong answer. In this way you eliminate the risk of habit-associating the wrong answer with the question, which is a trap that many (including me) have fallen into. Once you feel you can answer almost all the questions without having to refer to the books, you are ready to start taking the 'closed book' exam tests on AE.