Help with events? What are they?

So I want to finish Jester in some of his old Pinto Horse events from '96. I know most of them but there are a few he's done that I'm not familiar with. Here they are:

Bareback Equitation (English and Western)
Ideal Pinto English
Obstacle Driving (Is it like a trail or ranch horse course...?)
Parade Horse

And there's one I'm not sure about, that I don't know if he's done before. Its the costume class. I don't know anything about it. I'm making the assumption it has something to do with dressing your horse up in a costume, but what exactly do you do?

Bareback eq. Is doing a pattern riding bareback
Ideal Pinto English is probably a class reserved for pinto horses (like breeding stock, tobiano, overo classes)
im not sure about obstacle driving or parade horse

Costume contest is not based on your horse. You dress up in a costume and are judged on the best costume in the ring.

Okay, awesome. What sort of pattern do you do bareback? It shouldn't be a problem but if its something incredibly hard I probably won't be able to do it. His whithers are incredibly hard to ride on, unfortunately, and since the summer I've lost all the muscle in my legs. That's what happens when you don't use it. Hmph ^^

Have you ever done western horsemanship or english eq?
Its the same as those your basically doing walk,jog,lope,stops, and turns at certain points or cones.
You might also have railwork after the pattern.