How to set Nodejs App to my domainname ?

[phoenix254]

Hello everyone,
I would like to ask you guys that suppose i have an app that i devloped in nodejs and listening on port (3000) , in client side i have added (var io = io.connect();)and domain name is www.domainname.com
That node app I developed, I test im my local computer on these url:

   ** localhost:3000** [ok works fine]
    **localhost**       [ i can see my page also no error in console but in browser console i recive error http://localhost/socket.io/?EIO=3&transport=polling&t=1442659093522-0 ]
    **192.168.1.1**  [ i can see my page also no error in console but in browser console i recive error http://localhost/socket.io/?EIO=3&transport=polling&t=1442659093522-0 ]

So now if my app works with this url* localhost:3000* how can i upload on my domain (www.domainname.com). What should i do to upload my app and run on my domain ?
Please help me Very Important and also i am new in programming && i love programming;