Making a Dedicated Server for a Clash of Clans like game?

I am making a Clash Royale like game but don't know how to setup the server so that clients can connect to it and battle with each other. I know about setting up your own MasterServer but, don't know how to run it on an always running computer(as a dedicated server) and making the clients(running on android) to connect to it. Also, which ip address should client connect to? How to search for a player that wants to battle? How to battle with other client and no instantiation or gameplay will take place on server? I don't want to use any 3rd party application or plugin. Please help. Thank you.