I don't know why fixya sometimes posts solutions as clarification requests. Well then, here we go again:
You did not mention which ports or for which application you want to open your firewall. You can go here and look up specific applications or click on any of the links to get an idea how in general portforwarding is done for your router.
If you have any more questions, just come back here and leave a comment - I'm happy to help.
Answers & Comments
I don't know why fixya sometimes posts solutions as clarification requests. Well then, here we go again:
You did not mention which ports or for which application you want to open your firewall. You can go here and look up specific applications or click on any of the links to get an idea how in general portforwarding is done for your router.
If you have any more questions, just come back here and leave a comment - I'm happy to help.