Sarah Carter played with the 'harp flat on her lap or a table and she played at the end of the 'harp opposite the tuning pins. She did not play the melody, but strummed chords. Maybelle didn't p,ay Autoharp with the original Carter family, but when she took up the 'harp, she played it against her chest and she played the melody.

In order to play most melodies, you must change chords more often than you would for accompaniment. You can strike the strings in the general area of the melody note. You don't have to be dead on, because the strings next to the melody note are muted by the felts.

Many players, myself included, modify their 'harps to play diatonically(sp?) and create double strings, making the sound much richer. This is difficult to explain briefly, but I tune the strings not needed in the key of the 'harp down to the next lowest string and cut the felts to fit. This is how Bryan Bowers gets the rich sound from his 'harps. Unfortunately, you only get one or two keys per 'harp. That's why you'll see Bryan bring five or six 'harps on stage with him.
Some people also tune the diatonic 'harps to a "sweet" tuning rather than a "just" tuning. (Look it up)