If you need a haircut while in India, don't expect to make a Tuesday appointment. Hindu barbershops are closed because superstition dictates hair should not be cut then. Cutting your nails after dark, whatever the day, also is considered bad luck. And when interacting with locals, be sure to pass everything with your right hand, from keys to food at the table. It's a common courtesy that developed since locals would typically use their left hand to wash up after using the bathroom.