What is the easiest way to find job within UN humanitarian organizations?

Answer 1

Try a real humanatarian thing volunteer!

Answer 2

You can get your foot in the door of a nonprofit organization by becoming a dedicated volunteer or by applying for an internship. People who work for nonprofit agencies tend to stay. Therefore, if you were volunteering or interning when a position became available, and you had proven yourself already (through your volunteering or internship), you may be selected as a candidate for a position.

There is a good web site for browsing through job opportunities and I have listed the link below.