Nepal is a volume in the series Culture Smart!, "the essential guide to customs and culture." Most travel guide books tell you where to stay, where to eat, where to shop, what to see, and what to do. This one gives you some valuable tips on how to navigate the strange social world that you'll encounter: how to greet someone, when to stand, when to sit, what to wear, how to eat, how to address people, whom to tip, which hand to use, what to touch, what not to touch, etc. Most of all, it tells you what you might expect of native Nepalis.
If the volume on Nepal is at all representative of the series, anyone traveling to a destination covered by the series should pick up a relevant copy. It certainly won't prevent you from making a fool of yourself in every instance, but it is likely to head off more than one embarrassing incident.