Make sure you've got the camera in 24fps mode and use 1/48 shutter speed (max).
Keep the aperture open as far as possible (low f numbers like f1.8, f2.0) to limit DOF (you'll sacrifice a little in sharpness, but I'm not sure you'll be able to tell when shooting 24f)
Finally, load a Cine-gamma preset that will give you the widest exposure latitude.
You may want to have an ND-1 or ND-2 filter on hand to help keep the aperture setting where you want it, but you'll do ok with the built in ND filters if you're not splitting hairs.
I've also been experimenting with a Tiffen Ultra Contrast III filter on my XH-A1. It produces some very soft contrast images, but I'm not sure it's necessary, given the flexible settings provide by the XH-A1's presets.
The XH-A1 is actually pretty versatile, but you might have to do some research and lots of test shooting to get everything configured to your taste. Whatever you do, do not shoot in low light. Proper lighting (and lots of it) will make all the difference in the quality of your film. Finally, don't forget audio. Do not use the on-camera microphones. Use a good, off-camera mic and pay close attention to mic placement, audio levels, etc. Bad audio can ruin a great film.
p.s. There are sources on-line for preconfigured presets for your XH-A1