During your trip to Nepal, you'll be welcomed by adorably cheerful people. Less so in the very touristy sites. Respect the welcome you receive and be on your best behaviour by following their social codes, so that you avoid being seen as impolite and disrespectful.
The Nepalese are courteous and calm, so you'll need to follow suit...be polite, easy going and friendly. The Nepalese don't understand our Western tendancy to air our woes, particularly in public. So it's important, whatever the circumstances, that you smile and keep your cool. You'll also find during your trip to Nepal that daily life follows a certain set of codes that need to be respected.
For example, when you enter a religious building or home, it's customary to remove your shoes. Once inside a house, do not venture into the kitchen - it's out of bounds! If you're sitting down to a meal where there are no knives or forks, you use your right hand to eat, as the left is considered unclean. And never pick morsels from someone else's plate.
If you find yourself in front of a stupa, go around it on the lefthand side. Follow an anti-clockwise direction.
Never throw anything onto a fire as they are considered sacred. It's also impolite to point at someone or something with your finger. When seated, don't point your feet towards others. Don't be surprised if you're not thanked for a gift you offer, it's just not done in Nepal.
Clothes-wise, be modest. Bared flesh is not appreciated. Women are expected to wear long clothes, although short sleeved tops and cropped trousers are acceptable for men. PDA's are out...leave that for when you're alone.
In touristy areas such as Kathmandu, Bodhnath or Swayambunath begging is practised on an almost professional level. It's hard, admittedly, to refuse a child who holds out his/her hand for money or a pen. But it's important to resist the temptation, so as to discourage parents from sending their kids out to work the streets. At the most, give them food, but certainly nothing that can subsequently be stolen from them by thieves or drug addicts looking to pay for a hit. The best way to help is to donate to schools that will evenly distribute books and biros or to one of the many charities that are based in the country. Such organisations need as much help as possible, but your time and skills can also be of great benefit in Nepal.
*After the devasting earthquakes of April and May 2015 the country is slowly getting back on its feet. This article was written prior to these catastrophic events.