Eventing is so great because most everyone is practical and it’s more about getting the job done and having a good ride rather than appearances. Not that you shouldn’t look nice and well presented, but things like a black bridle with a brown saddle are unremarkable. Doing dressage in your jump saddle, if you wish to at the lower levels, gets done a lot too.
I just went all black with my tack: Black Micklem bridle, black Custom Saddlery dressage saddle; black Kentaur Eventer II jump saddle; black Prestige breast collar and girth; black Equifit and Roma boots for show jumping and cross country. The only color is on my horses’ ear bonnets which are black with bronze or gold piping since one is a buckskin and the other palomino. They both go nicely for dressage, show jumping and cross country in a Korsteel flexiflavored peppermint mullen mouth bit. My dressage pad is a white, no slip Equine Comforts Products pad and my jumping pad is a black, no slip, contoured Equine comfort products pad. I don’t use any other pads. I sometimes use an Acavallo wither gel pad.
KISS is my rule whenever possible.
My best advice is get your feet wet by going to schooling shows. They are wonderful, fun, low pressure events for sorting things out and honing yours and your horses’ skills.
If you’re coming over from hunters, you may already have a monogrammed tack trunk and such but if not and need a trunk, go get a 50 gallon Husky or Stanley from Home Depot to tote all your show gear in. You’ll see lots of them at an event.
A hanging saddle rack that fits on your stall front is a great thing to have and easily fits into your truck, which is easier than hauling a collapsible rack.
A bridle rack for you stall front.
A stall pick, broom and small garden wheelbarrow for clearing your stall post show.
An eventing stop watch to time your cross country run.
Your own penny/number holder that you’ll reuse at each event. Of course, a safety vest; mines a Tipperary. You can do all three phases in the same helmet as you’ll see lots of variation out there. I ride dressage in one helmet, but do show jumping and cross country in a billless Tipperary skull cap with a black CO cover. Some people like to let their freak flag fly on cross country and get quite colorful. So have fun with that if you wish.
A good sponge; a good brace like Vetrolin liniment post cross country run as I really don’t think you need to worry about icing your horse’s legs until you get to Training level. Rubbing alcohol to help remove any green spots from your horse’s coat should he lay down and get a poop mark or rub stain.
That’s all that comes to mind at the moment.