Before you start your trip, buy some good guide books. (Lonely Planet, Polyglott, Marco Polo, Reise KnowHow, etc.) This whets your appetite for travelling and offers a lot of useful information about the country you are going to visit.
Scan all your travel documents (passport, tickets, confirmations) at home and put them on a USB stick as a backup.
Bring a simple unlocked mobile phone with you. During the tour the driver can get you an Indian SIM-card for little money. This will enable you to make very cheap phone calls abroad and keep in contact with your driver.