Click the Advanced tab, review the warning then click Continue.
Click Port Forwarding (located below the Advanced tab).
Click the Port Forwarding switch to turn on or off.
If turned on, select the desired app(s) (e.g., DNS, FTP, HTTP, etc.).
Selected when a check mark is present.
If the app isn't listed, click Add a Custom Application (lower-left) then enter the appropriate info.
If turning off Port Forwarding, skip to step 7.