Via the Website Builder Files button you can add PDFs, MP3s, and documents that you can store on your site for your visitors to download.
Scroll down to the Create your website section and click on the Website Builder icon.
Click on the Login button next to the relevant package.
From the Design view, click the Media Tab, which is located in the left hand pane in the Design window.
You will see a gallery of files available to you. You can add additional files (up to a total file size of 10Mb). To upload your new file click the + Add link.
From the pop-up file manager window locate and click the image you wish to upload. Click the Open button to select the image.
Your new file is now available for you to drag and drop from the file gallery into your website design.