You'' need to go thru the documentation of your router for that. And it's help file.
Mine's very simple, I go the router main page, get to something called port forwarding, put in the IP of the Machine I want to see online or be seen across my network give the port number for the printer and that's it.
Windows has default ports for every service so all you need to do is just check out it's port list to get the list of services and ports.
Guiding you through the whole process will be very tedious and long.
Try a few things yourself and then let us know the result we'll take you on from there.Hopefully.