These directions are written for DNN 5.x and above, if you are using 4.x, just substitute the words "Edit Text" for "Edit Content" and "Text/HTML Module" for "HTML module"

1. Click to Edit Content on an HTML module.
    
2. Type the text that will be the link to the PDF file.
    
3. Highlight the text and click the "Insert/Edit Link" tool in the editor toolbar.
   
   
   
   
    
4. Click the "Browse Server" button.
    
5. Click "File ( A File On Your Site )"
    
6. Click the File Location drop-down and choose the folder on the server that you intend to put your PDF file into.
    
7. Click the link titled: "Upload New File"
    
8. Click the Browse button and browse your computer and network to find your PDF.
    
9. Choose your PDF and Cliked the "Open" button.
    
10. Click "Upload Selected File"
     
11. Wait for it to upload, and confirm that the filename is now shnowing in the "File Name" box.
     
12. Click "Use Selected Link"
     
13. Optional, to have the PDF open in a new window,
    Click the "Target" tab
    Change the Target setting to "New Window (_blank)
    
    
     
14. Click the OK button
     
15. Click "Save" at the bottom of the editor.