Dont be nervous! I was at first but I kept my nervousness under control and didn't show it I think Lucy caught on though and took care of me and she knewitwas my first time jumping. Now I love jumping! The reality is you will fall but that's part of riding you've just gotta get back up,dust yourself off and try again we are after all, equestrians!
Equestrianism; 10% luck, 20% skill, 15% concentrated power of will, 5% pleasure, 50% pain and 100% reason to remember you're absolutely insane to be riding a beast that big.