Glenn aside, I think wearing costumes does look a little dorky, IMHO. It’s best to look as you do in everyday life. People on the fence can identify with someone that looks like they do. Leave the glitter paint and torches at home.
Dress normally, stand up straight and represent America. I love The Flag and signs.
Based on all of the Tea Party events I’ve seen, 99% of the people dress in everyday clothes. I see far more weird costumes and hats at the Democrat and Republican conventions.