Actualloy, at least as important - wash your hands at EVERY OPPORTUNITY.
A lot of cross-contamination occurs at a Con, involving viral and bacteriological contamination from across the country and even around the world. You will be shaking hands with these people, touching books they have touched and so on. About a quarter of GenCon attendees I know have come away from GenCon with a major cold, fever or flu. By washing your hands regularly (and properly - not just a few seconds of hot water, but at least a 20 to 40 second wash with soap), you seriously reduce the risk to yourself and to the others you may be contaminating.