Join Date: May 2007
Location: Fairbanks, Alaska
I don't agree with not entering her in any classes until she is calm in the show environment. The classes are the more stessful part of the shows, and you need to give her and yourself as many opportunities as possible to get used to them. They are just outsided of her comfort zone still, but with time and experience, they will become old news to her.
Just practice relaxing yourself as much as possible. I agree with an extended warm up. I would say at this point, don't give her many opportunities to stand still, but keep her moving, flexing, and suppling, She doesn't have to work her until she is tired, just keep her mind busy by asking her to do various maneuvers and obstacles as spirithorse said. If you keep her focused on you, she won't have the time to get nervous and think about getting nervous and ready to go in to the arena. Give her little 30 second intervals where you allow her to stand still, and then move her out again before she has a chance to move without being asked. Gradually increase the length of time that you stand.
One thing that you can do, if you have a pattern class you are trying to prep for: look at the pattern, and then walk through it in your head, and on your horse. You can walk the whole thing on her, turning the designated directions, and just day the gate change or obstacle in your head. "walk, walk, walk...trot at ground pole...left lead canter...." I tend to do this a lot to help me prep for my patterns, and to keep my boy busy. This was our second show season, and the difference between this and last season was really improved; I can't wait to see how much more relaxed he is next season...It just takes time, expreience, and exposure.
Finally, in addition to her being an ottb, you have the fact that she was a barrel racer going against you. You are exacty right in thinking that while you are sanding outside of the arena waiting for a class, she might be anticipating a high adreniline run coming up. That would definitely be cause to prance and dance in anticipation. I would avoid doing any kind of gaming events, even for fun, until you have her fairly relaxed at the shows.
Good luck :)