Header images is a standard WordPress feature that SiteOrigin themes use for logo uploads. To upload your logo, navigate to Appearance > Header.
From there you have 2 choices. You can either upload your logo from your computer or you can select it from your media library. In most cases you’ll want to upload the logo from your computer. So select it, then press upload.
Ideally you should upload a transparent PNG, but a GIF or JPG image will work too.
Next, you’ll get the option to crop your logo. If you have extra space around your logo, you can crop it out, but in most cases you’ll just want to skip cropping.
Finally, press save changes to tell WordPress to use your newly uploaded logo.