Plug left and right mics into inputs 1 and 2.
Set up mic stand and angle mics 45 degrees towards one another.
Make sure that both input 1 and input 2 are set to +48V and the central switch is turned on. Use manual mic gain controls and move the dials to set appropriate recording levels for the piece you are recording.
In the camera's menu, set the input for channel 2 to input 2.