You just need to know the NetAddr of where you are sending the message, so IP address and port. The code below sends to a Fader on my iPad, but the message could go anywhere.
var oscFader = NetAddr("127.0.0.1", 61383);
w = Window.new.front;
c = NumberBox(w, Rect(20, 20, 150, 20));
a = Slider(w, Rect(20, 60, 150, 20))
Sending the entire Signal is a little trickier. This example just sends it to a local OSCFunc, but you can send the message wherever. The 2 tricks are using .as(Array) to turn the Signal into an Array and then the *, which takes an array and spreads it out into individual values (which is what the sendMsg needs.
a = Signal.sineFill(1000, 1.0/[1,2,3,4,5,6]);
~oscFader = NetAddr("127.0.0.1", 1200);
}, '/test', nil, 1200);