I am a HUGE fan of Stephen King. When I found out (last min) that I was going to a horror con, the only horror related costume I had was my old Carrie dress from Halloween many years ago. The dress is not 100% accurate to the movie, since I didn't have time to find a new one.
I pre-bloodied the dress the day before so it would be dry when I wore it. The day of, I strategically dripped blood on my face, arms, and in my hair. I used a large brush to help "paint" it on since just dumping it wastes a lot of the blood (it looked like a murder took place in my bathtub!)
I had fun with this costume and I hope to have a more accurate dress the next time I wear it!
Goriest costume at Motor City Nightmares 2012