Style - Upload Logo
Navigate to Appearance>Header. Select the browse button and upload your logo.
For best results, your logo should be sized at 1020px wide by 400px high before you upload. The logo in the Style theme is set for Retina quality, so you will be loading your logo at double the resolution and it will be sized down to 510px wide by 200px high.
How do I center my logo?
Navigate to Appearance>Editor and look for .title-area in this file. Change the width: 510px; to width: 100%;.
Next if you need to adjust the padding on the top and bottom to put it down or create less space, you’ll look for.header-image .site-header .wrap and adjust the padding: 100px 0 100px; to what you need. The first 100px is the space above the logo and the second 100px is the space below it.