Go to the Content Editor on your page where you would like to place a link to the file or document. 

Step 1 - Highlight your text (or select an image to highlight) you wish to set up a link in

Step 2 - Click the "Link" Icon

Step 3 - Click the "Browse Server" button

Step 4 - Select the folder your file is currently in (i.e. Files).

Step 5 - Find your file in the folder. If your file is not in the folder or on the server, go ahead and upload it into your folder by using the "Upload" button.

Step 6 - Once you find your file, double-click it.

Step 7 - Click the "Target" tab

Step 8 - Select "New Window (_blank)" in the drop-down field. 

Step 9 - Click the green "OK" button to save the changes for the link.