Reddit reviews Culture Shock! India: A Survival Guide to Customs and Etiquette

I, too, will be headed to India in a few weeks! I'm coming from the other side of the planet, tho, but I've been to India more times than I can count. As a foreigner, I can tell you that if you haven't experienced developing countries, it will be a smack in the face. The poverty in the cities is brutal, but if you keep an open mind and respect for foreign cultures, you'll find Indians to be extremely generous, traditional, warm, and friendly. Also, where there is poverty, there are also riches to be found, and bountiful. India used to be one of the richest countries in the world, and their artwork, crafts, and jewelry still reflects this.

Try and learn as much as you can about the culture before you go. I would recommend this book, my dad had to read it before my mom and I took him to India. Also, ask many questions. Indians will love to see your curiosity and will gladly go to lengths to explain their world to you.
Good luck! Sounds like an exciting trip!