You spend the entire interview being friendly, likable, and at ease while fluidly and competently answering the interviewer's questions.

I know that sounds like a trite answer, sort of like the How to Draw an Owl instructions[1]. But interviewing is something you can practice for and become good at. Or at least better at. There are quite a few good books on the topic.

That's not to say the candidates you're competing against won't also be likable. But I've interviewed lots of developers over the years, though, and if you're a developer who is competent technically who also interviews well, you'll be far ahead of most of the people you're competing against.

[1] http://knowyourmeme.com/photos/572078-how-to-draw-an-owl

I'm the only one from my country that apply for this position (how do I know? they tell me).

This interview process, is not the first process. before the interview, there is a "skills assessment" session, that I am passed.