Change menu position, above the header

Hi,
I’m no php Experte.Bevor I do something, I want to assure myself that it’s right.

So if I want to put the menu above the header, how do I do that?
In which file I look for? And what do I have to chance?
can someone help me?

Thanks in any case, for such a beautiful, responsive theme. I wish I could do more on programming languages??, like you.

regards
Stavros