Open a web browser like internet explorer or Netscape.

Enter the ip address of your router in the address bar of your browser. In the picture above the address bar has http://www.google.com in it. Just replace all of that with the ip address of your router. By default the ip address should be set to 192.168.1.1.

You should see a box prompting you for your username and password. Enter your username and password now. By default the username is admin, and the password is admin. Click the Ok button to log in to your router.

In the menu on the left hand side of your screen, click Advanced Settings. Clicking Advanced Settings will drop down a submenu. In this submenu click NAT/Special App. Setup. Which will display the following page.

Use the Protocol radio button to select the protocol type you chose in the PortTrigger application. Put the trigger port you setup in the PortTrigger application in the Trigger Port box. Enter the ports to forward into the Incoming Port(min.) and Incoming Port(max.) boxes. Put the lowest port number of the range into the Incoming Port(min.). The highest port number of the range should go into the Incoming Port(max.) box.

When you are finished adding these configurations, click the Apply button at the bottom of your screen. Be sure to save your settings and reboot your router before these changes take effect.

And that's it! You are done!