Where does the hem fall? it really all depends from there.
Leggings & cardigans are a good way to play with a simple dress. Boots are best for winter but flats work too. I’d be interested to see how thigh-high or over-the-knee socks looked with it.
You could always play with belts, or pretty fabric tied around your waist, too.
Does your mac come with iphoto? i know you can resize pics from there :-)