Navigating to Tools > Files > Documents, you can upload documents of all types to then use and link to from your shop. Uploaded documents can be public (thus linkable and visible to users) or private (not linkable and hidden from users).
All you need to do is select the file to upload, select public or private, and click ‘Upload’. The section to the right will display all the documents you’ve uploaded, with related information. If you click the name and URL of the document, it will be downloaded automatically. If, on the other hand, you want to delete it, click ‘Delete’. The document URL is used to allow your site’s users to download the file, so you’ll want to use it as a link to text and/or images.
The search tool lets you search for documents by file name.