Somethings that I have found work really well for me are:
1. When packing dress yourself and your horse. That way you wont forget anything completely major. Next go through your routine at the show and pack your way through it. I usually keep all my show things packed so that way all I have to do is grab the duffle or what ever and go. Don't pack as you see things, your going to forget tons of things.
2. If your horse is a braid shaker, like mine. Try using an aerosal hair spray and really soak the hairs. I know aerosal hair sprays are bad of the ozone layer but triggers spray leave white flakes on the mane. I have used mousse on my horses mane with decent results.
3. If your horse is constantly shaking out her braid I would reccomend gettinga sleezy and has a zipper either all the way down or to the throat latch. THat way you can put it on but not ruin the braid in the process.
4. Paint hooves the night before. I am always getting black on my breeches so by doing it the night before I am no longer ruining breeches. Plus you will be able to spend more time on them and get it perfect with touch ups in the morning.
5. Visualize. Get up to the arena early, see the arena, where cones are set up, close your eyes, and run through the pattern perfect. Then run though it again correcting problems you know your horse is going to have. Then visualize it perfect again. I strongly believe that this works. Call me crazy but it works. This will also calm you and get you focused.
6. Act confident. It shows and if you act confident you will seem confident, something judges like.
7. Enter ready to win. Don't enter slouchy or badly. Judges pick out thier horses as they enter the arena. Entering is more important then you think. I always make eye contact with the judge before walking in, nod, and ignore them the rest of the class. Tell them that your there and let them look for themselves. You shouldnt have to stare at the judge through the whole class.
8. When in the line up keep showing, even if you think the judge has handed in the card, keep showing. You are not done showing til you leave the arena. I find it annoying when girls stop showing just because they think the card is in. You never know, there could be a problem with the card, it comes backs, and the judge has to look over the horses again. Which one is going to get placed. The one slouching or the one standing up nicely.
9. In the end though ride you have fun. If you focus too much on the ribbon and winning it shows. By acting carefree and riding to have fun, the ribbons just have a way of rolling in.