Good luck with that, easy and making multiplayer with C2 are not even in the same geography... Tutorials on simple nuclear fusion may be a bit more realistic :) Especially since C2 has no built in support for multiplayer. Just saying, I doubt you will find an easy tutorial on it as there is nothing easy about this particular topic when it comes to C2. If you search the forums you will find some examples, but none of them are easy or short, they pretty much all require heavy coding and running your own serverside system for it.