Welcome! Glad that you have joined us!
I know that there are ideas and Cathy and Kay have done lots of promotional things. Cathy set up a display that had CMHR informational handouts like our brochures that she put in high traffic areas (with show approval) and used banners that she managed to get displayed when she sponsored classes. So just putting up a display like a poster with a few pictures of rescued horses shown on it (there is a post with Nell's pictures that you may be able to use, and Ginny and the others may have some pistures along with the CMHR web site) would be of benefit.
Also, see if you can get a CMHR cookbook to display, and print out ordering information for it. Also, get yourself a CMHR T-shirt to display as well (or wear it) and info on how to order that as well. (I don't know if you can get these items sent to you on a "consignment" type deal or not... You may want to email Kay to discuss that with her. We have had some issues with "consignment" type of situations in the past, so are very cautious about it.)
And thanks for thinking of CMHR when you are there!