Searching for the perfect prom hairstyle? It’s a good idea to choose your hair and makeup after you’ve picked out a dress. A shorter, cocktail-length dress probably wouldn’t go all that well with a very formal updo. A dress with a lot of details works better with a simple style and a minimum of hair accessories. Long, dangly earrings look great when you’re wearing your hair up, but may get lost in a tangle of waves.