The answer depends on what colour the national team jacket is in your country. If the team wears red, it's a faux-pas to wear the same colour that those team members have worked so hard to earn. The same applies for non-red team jacket colours in other countries as well, though some countries use common jacket colours that are distinguished by coloured collars or patches.
Brightly-coloured show jackets are becoming more and more popular in the jumper ring, making colours like red more widely available than they used to be. As a result, you will occasionally see a rider wearing the same colour as the national team, but while it is not against the rules in every country, it is still frowned upon by most. Check the rules of your national federation before you go out shopping, and do your best to avoid the same colour combination as your national team (both jacket and collar) even if it isn't explicitly written in the rule book.
How can I keep the cheeks on my hackamore bridle from going into my horse's eyes?
This is a common problem with hackamores, exacerbated by the curb action that can swing a seemingly well-fitted bridle towards the eyes.
If your hackamore is adjustable, you can try making it wider so that the cheek pieces attach further away from the bridge of the nose, bringing them slightly away from the eyes as well.
If your hackamore is a fixed size, the trick is to tie the cheek pieces away from the eyes by adding a string or strap to the bridle. Simply tie a piece of conservatively-coloured string (number string works well, or anything else like a shoe lace that isn't likely to rub) from about halfway up one cheekpiece, under the jaw and up around to the other cheekpiece. Make it tight enough to keep the cheekpieces out of the eyes, but not so tight that it will rub or restrict the horse in any way. A leather strap of an appropriate length could also be used to the same purpose (spur straps, a shortened bradoon hanger, etc.).
If you do a Google image search for Russel Skelton Royal Fair, a couple of examples will pop up showing what the set-up should look like.
Why aren't hunter score sheets made public?
Quite simply, most people would not understand them if they were. Unlike dressage with its single score sheet per horse and myriad comments, a hunter class is scored with only one line of symbols and notes per horse, necessitating the use of symbols that each judge finds fastest and easiest to use, and which can vary from judge to judge. Because hunter judges don't have scribes, this system allows the judge to keep as much focus on the horse as possible with minimal writing and no delays between rounds for writing comments, as well as the ability to compare rounds quickly without flipping pages.
Any comments are usually more for the judge to remember the round for comparing scoring than to comment on every aspect of it, while the more obvious symbols such as the shape of each jump should have been felt and seen by the rider and coach, anyway.
Which type of hair net is the correct choice for the hunter ring?
There are three categories of hair net marketed for riding: traditional two-knot hair nets, one-knot hair nets, and no-knot hair nets. The two-knot hair nets can be uncomfortable because of the multiple knots, but this also keeps them tighter and less baggy than the more comfortable one-knot type (no pressure points if the knot is put in the back but the hair net can puff outwards if not tucked in). No-knot hair nets are like bands, open at the top of the head.
Because only the edge of the hair net will ever show under your helmet anyway, there is no one correct choice. Choose the option that is most comfortable for you while still allowing you to keep your hair neatly contained.
What should I do if the zipper on my boot breaks?
If your federation's rules allow you to compete in your schooling paddock boots and half chaps, you can switch to those if you are able to clean and polish them to show ring standards.
If you don't have a back-up set of boots with you, you can use electrical or duct tape (preferably black) wrapped around the boot to keep it closed. Zippers tend to break at the worst possible times, so black tape is a good thing to have in your tack box just in case. Try to have the zipper repaired as soon as you can, but everyone is likely to be understanding of inconspicuous tape in the meantime because it has happened to so many.