I'd hold off on the parade until you get leaving home down first :)
If possible, is there a friends place or a non show day arena you could make a quick trip to? Just getting them off the farm and used to the trailer if they haven't spent a lot of time in it, and going to calm new places. Once that's conquered, then head out for a horse show. If you plan on leaving your horse trailer tied, make sure you do it a couple times at your trial location.
The most important part of the experience for the horse is you and your demeanor. If you're anxious and expecting something to go wrong, there's a better chance it will. Obviously not to let your guard down completely, but it's a lot easier to be confident in your horses behavior if you've had the chance to set the tone for the experience controlled and gradually.
I also wouldn't be concerned about a show being upset about you coming and not showing. If you were a trainer going to a large major show, where the stalls were sold out and bringing in a full trailer of green horses and not showing one, then yes absolutely I see the frustration. But good show mgmt also knows that if they can provide a good experience for you to come, hang out and grow into it that you could become a regular entry paying shower there too.
Last edited by Coffeejunkie; 05-23-2013 at 04:21 PM.
Reason: Have not had enough coffee, can't make words :)