Ann & Rob
Not wanting to put you off but a big county show is a big first step if you haven't shown before.
Sorry, but I have to disagree. If you want to try your hand at showing, just go for it. My first, a good few years ago now, was the Royal Welsh Smallholder Show (as it used to be known) - hardly a small show. My gilts were too old for the July class, so went into the sow class, but still came away with a 2nd and a 5th - and they weren't trained for the ring, either.
You'll find that most pig exhibitors are incredibly welcoming to newcomers, and you won't be short of help.
I'd recommend starting off with a sow, rather than younger, flightier pigs. January-born ones can be a nightmare - particularly if they're small enough to get under the barriers used to create the ring.
Good luck, and message me if you want copies of any of the stuff I've written on starting in showing for Country Smallholding magazine. Happy to help if I can.