I've actually done most of these. None of them will win you a prize, but I found them to conform the expectation that I wore a costume without making me do anything too expensive, difficult, or itchy.
1) Wear jeans, a t-shirt, and sunglasses. You're a fifties hoodlum! Embellish with cigarette pack in sleeve, hair grease or pony tail.
2) Wear white. Buy small dolls (ideally in international costume) and pin them to yourself. You're the "It's a Small World Ride." Embellish by playing or singing song if feeling hostile.
3) Wear pajamas. Carry a stuffy animal. You're a small child
4) Find a similarly lazy colleague. Wear the same thing as each other-- make it an outlandish color combination or very specific in another way. You're twins!
5) Wear a Superhero T-shirt under your regular work clothes, leaving a couple of buttons undone. You're showing your secret identity!
6) If there is a celebrity you resemble, wearing something vaguely appropriate and a name tag.
7) If you and a colleague look similar enough to each other that people confuse you, go as each other. Again, use name tags.
Go as the color of your choice by buying a can of colored hairspray and dressing to match. If your colleagues are dense, this works best if you go as "The Color Purple."
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Landon Bryce
www.thAutcast.com
a Blogazine for the Aspergers and Autism Community