Find a local class in the Hindi language. If you are starting from scratch and have no knowledge of the language, then the easiest way to learn Hindi grammar will be from a teacher who speaks the language.
Check the course offerings at your local community college or at any college or university in your area. If you cannot find a school that teaches basic Hindi, then try your local public schools for adult or continuing education classes.
Try using Hindi grammar books if you cannot find or afford a local language class. You can find these books on the Internet or through your local library. If your library branch does not have Hindi books, then you can ask a library to borrow some through an inter-library loan.
Use the Internet to learn Hindi grammar. There are multiple Hindi grammar sites such as HindiLearner.com, HindiLanguage.org and MyLanguages.org. Some websites, such as HindiLearner.com, offer online tutors who are native Hindi speakers.
Compare the lyrics to songs in Hindi with their English translations. You can use a website called Bollywood Lyrics, which lists the original Hindi lyrics to Bollywood songs with English translations of each songs. If you have a basic knowledge of Hindi grammar, you can enhance your comprehension by inferring grammatical concepts from songs.
Ask someone in the local Indian community if there are any tutors willing to teach you Hindi grammar. If you are a college student, check the bulletin boards in your language department's office, since tutors often post ads there.