Header centered

Hiya,

I have two questions.

1: http://i.imgur.com/f2pXbTD.png
The logo here is floated left, but I want to float it in the middle. I don’t know how to do this. I can only float it left or right I believe. Anyone?

2: http://i.imgur.com/2I9nH1P.png
The menu is also floated left, but like the first question I want to float it in the middle. Someone?

Kind regards!