Establishing your goal for learning Japanese will determine which type of textbook you purchase. For example, if you are learning Japanese to travel to Japan for a short period, then you would not need a textbook that includes sections on writing Japanese, but you would need to learn travel phrases and how to read common signs. As many teachers will tell you: "Learning a new language is about goals before anything else."
Read reviews of various textbooks. There are many Japanese course books to choose from, and luckily for you, many have reviews available online.
Choose by format, not by title. Examine the layout of the course book, paying special attention to the following considerations: 1) short chapters help you stay motivated by providing frequent chances to feel accomplishment and progress; 2) sections organized around a theme (rather than a grammatical issue) provide a sense of real-world application that can keep you focused on your learning goal.
Purchase three different colors of highlighters: one for vocabulary; a second for grammar; and a third for usage or supplementary notes.
Buy two notebooks: one for vocabulary; one for grammar.
Organize your vocabulary notebook around a style of association that best helps you remember. Some students organize vocabulary notebooks according to synonyms and antonyms, themes (i.e., business, home, travel), whereas others may use sketches, pictures or doodles as an aid to memory. No matter which method you choose, the key is to avoid simply writing down words in the order that they appeared in the course book.
Read the title and introduction for each chapter in your course book to get a feel for your estimated learning progress.
Write your learning goals at the top of the first chapter before you begin studying. Your learning goals should be as specific as possible: what you want to learn in this chapter and why. Having (and meeting) specific goals will help keep you motivated, provide a sense of accomplishment and focus your mind on the learning task. Repeat this step for each chapter before you study.
Make a note card for each chapter. On the note card, write five to seven key vocabulary words from the chapter. Keep this note card with you and review throughout the day. You should make a habit of reviewing it before you go to sleep and just after waking up.
Read each chapter twice --- 1) to achieve general comprehension, highlighting vocabulary, grammar, and usage notes; and 2) to review and confirm your understanding.
Use flashcards to review and quiz yourself intermittently on vocabulary and grammar. You might want to check into a few freeware flashcard programs available online .
Rewrite example sentences from the chapter in three different ways to apply to your own life.
Mimic the actions of vocabulary (when possible) as you study: physical movements help the brain to remember new words.
Go back and check your learning each week. Pay attention to the learning goals you set at the beginning of each chapter: Are you meeting them? Why or why not? Adjust your future study habits and schedule according your self-assessment.
Consider subscribing to an online language, course such as Japanese Pod 101. Such courses provide valuable examples of the living language, as well as useful learning and reviewing tools.
Read aloud to yourself three times any example sentences, sentences you have written, or vocabulary items.
Make an audio recording of yourself pronouncing the vocabulary items or speaking sentences in Japanese, followed by a pause, and then followed by the English translation. Listen to this audio outside of your structured study time, and try to anticipate the translations. Repeat the Japanese as you listen. As the BBC advised on its Language Education website: "Make your learning an active part of your life ... you're likely to remember 20% of what you read and 30% of what you hear ... and a staggering 90% of what you see, hear, say and do."