Exporting mission to multiplayer?

[Herpyderpy987]

This is my first time on these forums so i hope you can excuse me if i'm posting this in the wrong place / wrongly.

But anyways, onto my problem.

I learned the basic's of the editor how to make units move, make simple battles e.t.c, but, my problem is:

How do i export the mission to multiplayer / coop? Let's say i already have the mission made everything is good, except i don't know how to export it to multiplayer / coop.

Any help would be appreciated.