Well assuming you connect your phone to your WiFi you do that in your router. Simply log into it, go to where it manages ports and choose TCP and UDP along with the port number then assign that to the IP that you have on your Android.
Details for tutorial can be found here: https://portforward.com/router.htm
Just find the model of your router there and follow the steps to get the idea how to do it, assuming it can be found.
And what about being stuck? What exactly is happening? If the sound is working but he can't move then it's 99% wrong MAC address in PPSSPP, just click it a few times and it should randomly generate a new one for him; do it before he gets stuck though
Here is one example how it could look like in the router: http://i.imgur.com/gIfRJlE.png
It seems like you are posting the same thing in different threads, don't do that :o
Details for tutorial can be found here: https://portforward.com/router.htm
Just find the model of your router there and follow the steps to get the idea how to do it, assuming it can be found.
And what about being stuck? What exactly is happening? If the sound is working but he can't move then it's 99% wrong MAC address in PPSSPP, just click it a few times and it should randomly generate a new one for him; do it before he gets stuck though
Here is one example how it could look like in the router: http://i.imgur.com/gIfRJlE.png
It seems like you are posting the same thing in different threads, don't do that :o