Just booked a big Maternity event! ideas?

I just booked a big event in Fort Worth called the Art of Birth Red Tent Event. There will be all things related to giving birth and pregnancy. There will be a Henna artist, a photographer, and a belly caster. I'm gonna do LIVE PAINTING! So excited!
Trick is... they aren't charging a booth fee, but ask that I donate part of funds. I can't charge full price ($55) because I would only be able to do like, 5 people! I can lower it to like, $20, and just do easy quick type art and get more ladies coming through... Do you think that would work ok? what kind of "quick" art can I do on a belly? name banners....easy island sillouette...butterflies....etc. Other ideas??

http://www.rainbowcreation.nl/html/bellypaint/bellypaint-foto-1.html

http://www.bodymention.nl/viewer.aspx?view=bellypaint

You have two options, you can paint the day of and have less time to interact with your future customers or set up tons of displays of your work and be there specifically to book bellies. If you were to do that option, take a model and paint a very detailed design live. Allow them to see what you can do in person.

Doing the quick paintings might make you a couple bucks the day of the event, but you might have been able to book all those $20 bellies as $55 bellies if you were more focused on making bookings and less on getting as many people in the chair as possible.

Also, you might be able to do both. I'm way too scatter brained to work that way, but my mom is the type of person who could pull it off so it's all in how you know you work.

I'd offer some quickie designs, maybe w/o a base. Do flowers, butterflies, etc. But also show the more detailed designs & push to book future high end bellies.
Kindof like WM said:-)