(http://portforward.com/english/routers/port_forwarding/Dlink/DI-524/DI-5240.jpg)
In the picture above the address bar has http://www.google.com (http://www.google.com) in it. Just replace all of that with the internal IP address of your router. By default the IP address should be set to 192.168.0.1.
(http://portforward.com/english/routers/port_forwarding/Dlink/DI-524/DI-5241.jpg)
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 blank. Click the Ok button to log in to your router.
(http://portforward.com/english/routers/port_forwarding/Dlink/DI-524/DI-5242.jpg)
Click the Advanced button near the top of the page.
The menu on the left should change. In this new menu, click Virtual Server.
(http://portforward.com/english/routers/port_forwarding/Dlink/DI-524/DI-5243.jpg)
Put a dot into the Enabled radio button.
Enter the name of the program into the Name box. It doesn't really matter what you put into this box, but something that will remind you why these ports are being forwarded would be a good idea.
Enter the ip address to forward these ports to into the Private IP box. If you are forwarding ports so you can run a program on your computer, you should enter your computer's ip address into that box.
Use the Protocol Type drop down box to select the protocol type of the ports you are forwarding.
Enter the port to forward into the Private Port and the Public Port boxes.
Put a dot into the Always radio button.
When you are finished, click the Apply button.