What type of show & what kind of classes are you wanting to do? I think if you go to similar type show just to watch ,helps alot
. See how people prepare their horse & themselves. Going to your first show with someone that has done it before is also very good they can help support you,show you the ropes & hopefully introduce you to some other people.
Going by yourself is more difficult but sometimes is only option
if so go with open mind,ask questions were you can, don't go with any expectations to do any big winning. Just go try have fun,be happy with having your horse & you make it through a class....you can come out & say yes I did it!! If you do well placing that is the icing on the cake
Make it a positive experience for you & your horse,knowing you did your best your first time out & take note/learn from any mistakes so you can be that much better next time round!!