Logo Symbol

Hello and good morning,
i am trying to configurate the theme at the moment and hope you can give me help.

I want to setup my own site like the shown one on your website, that means that i want to have the logo symbol on the left and the menu on the right above the slider.

where can i upload and put in my own logo symbol ?
how can i make the menu a bit smaller ?

here is my page: http://ase.wedl.nu/

thanks a lot for your help

kind regards

markus