1. Open terminal
2. sudo vifs
3. Add a line in the following syntax:

   1. <hostname>:/<sharename> /Volumes/<sharename> url automounted,soft,url==cifs://<username>:<password>@<hostname>/<sharename>

4. Dissection of parameters:
   1. <hostname = the hostname/IP of the NAS
   2. <sharename> = the share name being served from the NAS
   3. /Volumes/<sharename> – should match the sharename to avoid naming conflicts with Finder trying to auto-mount the same volume
   4. <username> = the CIFS username you’d like to use
   5. <password> = the CIFS password
   6. <hostname> and <sharename> should match the above variables
5. To re-hash the mount points, run: sudo automount -vc

Further reading/troubleshooting

1. See this guide for more information on auto mounting, including talking to a Windows AD domain