You need some kind of thread stand to feed the thread to your machine. I have one from Superior Threads that is adaptable to all sorts of thread situations. However, for one time use, what you might want to try is this:
Place the cone in a canning jar behind your machine. Find a large safety pin and tape it, closed, with the round "eye" up, to the read of your machine near where your normal thread spool is. Thread the serger thread up and through the "eye" of the safety pin. This will simulate thread coming off a spool. Thread the bobbin as usual. (You may need a thread net over the spool to prevent thread from falling and puddling under the cone, but I would try without first.)