Adding documents to your website can easily be done. This process is the same for any pages/content types that use a WYSIWYG editor to add content in PSB. 

First make sure you are logged in to the Site  Click Manage and then Content on the Admin Toolbar Window.   Go to the page on your website where you want to add a link.  Click Edit in the admin tabs that appear right below the title area. Within the WYSIWYG area in the edit screen, highlight the content that you want to link a document to and click the Link button in the WYSIWYG toolbar.  Click Open File Browser within the “Add Link” dialog box.   In the File Browser, click Upload and the “Add file” button to search your computer for the new document you want to add.   Click “Save” and check that the link appears properly in the WYSIWYG editor.