Just don't be rude with everyone and don't take things too seriously. This is my motto when I go to different places where I don't know the culture. There are universal actions like smiling or frowning that everyone can understand.
I agree with you about the universal gestures like smiling and frowning, as well as nodding and shaking the head to say yes and no. But I am not sure about Indians. Sometimes an Indian say "acha" (meaning yes) while shaking his head.