I like to use an SM57 and point it to the 12th fret of the guitar so the sound isn't too boomy. As an recent experiment I tried to create the acoustic sound of the first America album and this setup, along with my Martin dreadnought worked well for doing that.
My other tip is to listen to good acoustic music for inspiration. My suggestion:
https://www.youtube.com/watch?v=gDZbpEgQ6i0