1. Be scary as possible! Use prosthetic make up. Here's an example.
2. Veer away from the traditional scary looks. There are lots of famous villains and weird characters. Dress like them! Here are samples. Vhong Navarro did Edward Scissorhards in today's It's Showtime Halloween special.
3. Go grand - dress like a robot! I had an officemate who dressed like Bumblebee once. He won the contest of course and everybody suddenly wants to have a picture taken with him. The only problem was he had trouble eating or even sitting haha... Shaider? (gosh, this tells my age! haha)
4. If you don't want grand and you have little time, go for characters you know - your childhood heroes. You can dress like sailormoon, zorro, etc.
5. Don't go alone - dress as a group ensemble! It's more fun to be silly with other people =p You can dress as the Addam's family, star wars, etc.
But if you really want crazy - you can come as you are... hahaha =p
Happy Halloween guys! =)