Hair

• Hair should be very simple, and if possible, a little greasy -- use hair gel to increase this effect if necessary. Avoid fashionable hair styles and coloring -- the classic female nerd hair style is pigtails. Always have two, and tie a pink bow around the top of each one. If your hair is not long enough for pigtails, either use a wig, or go for a side part, again using plenty of hair gel.
  
  

Clothes

• A nerd outfit can feature either a skirt or pants. For the skirt, get a plaid one and wear it with either white tights or knee-high white socks, and black shoes -- nothing too fashionable. If you want to wear pants, buy a size that is a little too short, exposing the ankle. Pull the pants up higher on your waist if necessary, and wear suspenders in place of a belt.. Wear these with a white shirt buttoned up fully, and either a bow tie or a normal tie.
  
  

Props

• The main prop to wear in a female nerd are thick, black rimmed glasses. If you don't wear glasses yourself, buy a fake pair with clear plastic lenses from a toy or costume store, or buy a pair of sunglasses and push out the lenses. Carry intellectual books and folders too, because a good nerd is committed to her homework. Novelty protruding teeth can also enhance the nerdy look.
  
  

Attitude

• Avoid being what is typically considered "cool." Hunch your shoulders when you walk, and speak in a high-pitched voice. Work on an annoying, nasal laugh. Quote Star Trek as often as you can, and make the Vulcan salute to people (index and middle finger together, ring and pinkie finger together, palm facing the other person) while stating without a hint of irony, "Live long, and Prosper." Regularly allow your glasses to fall down your nose a little, so you can push them back up with your index finger.