Again this is probably going to require long control horns, and short servo arms. Make sure elevator throw is exactly equal in both directions. Initially setup the rudder to use its maximum available throw. It's important to setup the rudder with the best mechanical advantage possible to ensure good resolution and power. You might adjust the throw later on, but for now get as much as you can.
First flights are sometimes nerve-wracking experiences.
Just get the airplane up to some reasonably high altitude and get it trimmed for level flight. Get a feel for the aircraft's control throws. You'll want to adjust these mechanically once you land. Initial trim on the rudder should also be performed now. Fly directly up wind, and straight away from you if possible.