For the girl who's had her fill of girliness & tiaras for one night: throw on a colorblocked top and dark, distressed denim, and smudge your eyeliner. You'll be comfy, and sleek in a sort of art-y way.
For the girl who still wants a "look at me!!" outfit, and who never is not wearing heels: stand out in all the pictures by print-mixing, but be sure to pick fabrics that aren't too precious and shoe with a chunkier, lower heel.
For the girl who wants the comfiest option out there: a t-shirt material dress, a moto jacket for warmth, a crossbody bag and low wedges that are often easier on feet than totally flat shoes. That's the equation.
For the girl who still wants to feel like it's a party, damn it: wear something sequined, like this little jacket. Over a basic dress or just with jeans and some red lipstick, it'll make you feel glamorous well after prom's over.