Reply To: Upload .PNG file to header?

Add this to your css for the logo –

.site-title a {
    background-position: center top !important;
}

For the nav you’ll have to make a some adjustments to your css. First on line 1942 – .genesis-nav-menu you’ll need to add text-align: center;

Then on line 1955 – .genesis-nav-menu .menu-item you’ll need to change the float: left; to float: none; and add display: inline-block; to the code.