Bring universal plug & voltage adapter kit for your electronic device.
Always use some tissue paper & hand sanitizer.
Insist for running tax. After 10pm it cost double however it's common accepted norm.
Avoid displaying foods around monkey temples.
Support Non- Plastic and help make a better and clean place.
Be sure to exchange back all the Nepalese currencies before you back. It is not accepted after leaving out of Nepal and it's against law.
Do not touch someone's head or sit showing bottom of your feat towards them which is considered a rude.
Food safety and avoid water that is not bottled or boiled and also avoid raw vegetables and pre cut fruit as much as possible.
Do not give money to beggers that you see on street which encourages them to beg for more. If you really want to support please childcare in Nepal.
Do not trek alone. There have been numerous lost of solo trekkers in recent areas. This applies to everyone but especially women that are traveling single.