Watch the film "Avatar," where the Na'vi language originated, and focus on how characters speak and pronounce words in the language. Pause the movie each time a character speaks in Na'vi and repeat what she said to get a feel for the language. You can also use subtitles to learn certain phrases spoken in the film.
Visit learnnavi.org, a fan-made website that contains several tools to help fans learn the Na'vi language. Tools on the site include a a copy of the Na'vi alphabet, a Na'vi number chart and a guide to Na'vi pronunciation. It is recommended to start learning the language by studying the alphabet and number chart and mastering pronunciation of the language's letters and sounds.
Use the guide of Na'vi phrases, vocabulary charts and Na'vi-English dictionary on learnnavi.org to master new vocabulary words. Nearly all of the guides, dictionaries and resources on the site are downloadable, so you can print them to take with you wherever you go.
Find a friend or relative that is also a fan of "Avatar" and who also wants to learn Na'vi. Practice your pronunciation with them or learn new vocabulary words. You can also create flashcards and then quiz each other.