All linking is done through the linking bar. If you want to link to a file, select the text you want to be the link and press “Insert/edit Link” button 
. This will open the linking pop-up window that allows you to hyperlink to a page, file, or email. If you want to link to a file, hit the “Browse” button 
.
The files on your server will be displayed in a new window. You can either select the file you wish to link to or upload a new one. To link to a file existing on the server, click the file you wish to link to and click “add.” If you wish to upload a new file to the server, at the bottom, there is a box with “Browse” and “Upload file” buttons. Click on the "Browse" button and simply browse to the file you wish to upload and then click the “Upload file” button. Finally click “add” once the file is uploaded.
The file URL will now be in the URL text field. Finally, hit the "Insert" button and your link will be inserted into your text.