You could always try one of those home decorating photo editors where you take a photo of your house and/or inside rooms etc and manipulate it with different colours. I have one I got at HD put out by Glidden paints I think but it doesn't do outsides and it's a bit of a pain to work with. I think there are better ones out there. I know I've seen some on other sites where people show their houses all sorts of different colors, added plants, added shutters etc, quite amazing. The safest route is to leave the trim white or have the colour you painted the clapboards darkened for the trim, that is if you're not confident or sure.