I used to be a big fan of Meguire's Quick Detailer until a couple of weeks ago when I tried Black Magic's Quick Detailer. I had heard a few people on here raving about it, but I blew it off because I was such a Meguires fan. Store was out of Meguires, so I broke down and tried it.
This Black Magic Quick Detailer is amazing. It blows Meguires quick detailer away. It looks like an oil when you first wipe it on, but its not the least bit greasy. It lifts dust without any worry of scratching. It removes bug and water spots like nothing I have used before. Wipe on with a microfiber towel to remove any spots/dust, then lightly buff with a dry microfiber to a perfect shine.
As you can tell I'm a huge microfiber towel fan too.
If you get a nasty bug mark on the trip, just don't try to rub it out using any pressure. That will scratch your paint. Just keep re-spraying the spot and lightly keep going over it. If there is still a mark left, use your polish lightly, and then re-wax the spot. If you can pick up a cordless buffer, that would be a great bonus tool to bring with you.
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47999
It just depends on how detailed you want the car to be.
For me I'd go with the following:
1) Show prep at home (clean, polish, and multiple coats of favorite show wax, etc).
2) Pack your show supplies (a duster (California, Swiffer, etc), Black Magic Quick Detailer, your polish, your wax, a bunch of microfiber towels, cordless buffer, and a car cover in case of rain).
3) When you get there, dust off the car, touch up with the detailer spray, and then put one more coat of wax on if you have enough time before the showing.
4) Go check out the other cars at the show, and have a good time.