Start small and when you get really confident you can go higher:) it's always good to have a practice at the height you will be doing at the show at home!
Relaxa, respira e diverte te! Acima de tudo acredita e não te stresses muito depois de veres a prova nem no aquecimento.. os cavalos sentem essas coisas 😉
I agree with Sarah, just have fun with it :-) remember how hard you've worked to prepare in lessons and be confident as you step into the arena!
Just have fun!! Make sure you learn your course(s) early so you don't have to worry about remembering them, and try to relax as much as you can:)