For some reason my horse lands off a jump and dives to the right. I know what you're thinking, it's because I have no leg. Yes I do. I squeeze HARD with my right leg, and then give him a little tap if he doesn't listen. It usually help a tiny bit. Now, due to this, I have turned to joyously pulling on my left rein. Great. So now we go around the corner after a jump with his head bent to the inside and shoulder shoved out.
Dressage darling! Dressage! Dressage is a strooonnggg asset to have under both of your belts. Or girth
Good for you for recognizing your contribution to this equation and for realizing what is going on and what needs to be fixed. It's the how that is the most difficult.
Have you looked into starting Dressage lessons? You would be amazed at how much this will help, aid and change the way the both of you go - to improve your performance while jumping.
First, he is unbalanced, your horse is coming off of the fence heavy on his forehand, he is plowing on his shoulders with all his weight. There are many variables as to why a horse is on their forehand - lack of balance, rider not aiding horse to rock back, riding not riding back to front and etc, etc, etc. This is why I emphasis dressage.
I can throw in suggestions as to what to do while over the fence, but that isn't going to fix the real issue, you need to go back to basics, which you will find in the world of Dressage.
My guy just came off of stall rest, which he was on for the majority of Jan. We're focusing alot on dressage. Building his mucles back up, balance, getting him round, soft, supple, on his back end, engaged, and MY FORM most importantly *our horses reflect 100% of what we do while in the saddle* - then, once we achieve that on the ground, we'll incorporate that over fences.
Spyder will definitely beable to help you out with advice, and Anabel - give those two a shout.