Always be confident and trust your horse. I've been jumping for quite a while now and these are some tips: heels down(always), look forward, straight back, don't stare at the jump, and don't jump a jump that you're intimidated with especially if you're a beginner. And lastly ALWAYS HAVE FUN! I love jumping and I'm happy that you love it too. When you're skilled enough to show then try going to smaller shows first and then bigger local shows (don't go to a rated show for your first show).
I hope this helped!