If you don't like to wear costumes, get the audience members to wear them. Better yet, get the "big shots" to wear them and you will probably be the hit of the meeting. I was doing a customer service talk for a pizza franchise and I had one of the senior managers march into the meeting wearing a filthy, doctor's lab coat with ketchup all over it (fake blood). I had another senior manager come in with a crisp, new lab coat. I asked a simple question, Which manager would you like operating on you? Of course, all the junior managers yelled out that they wouldn't let either one of these people operate on them. Everyone was laughing and joking around, but the point was made. They must keep their employees looking clean and neat because nice customers won't want to be served by grungy food service workers.
Costume characters can be hired to hand out fliers at your event, entertain, and generally create an air of fun and excitement. The local heart association has a "blood drop" costume they use when they are soliciting funds. There are literally hundreds of costumes available through costume shops or via mail order. Just make sure, as always, the theme of the costume matches the theme of your presentation or event.
The best marketing techniques...designed especially for speakers!