Are you just forgetting to sit when you should when running? I have a really funny and kind of goofy way to keep that in mind. I told my lesson kids that and it's how I remembered to drop my hand, hold the horn, and sit deep in my saddle..
Think of it like this..The horn is like a wii remote. You have to hold it and lean to "play" the game right.. I wish I could show you, it makes so much more sense. When you're working at home make it a habit to remember to use the "remote" when turning..I actually started making like sound effects to remember and made a game out of it, this helps even though it sounds stupid...My sister will "lope" around on her feet and make the hand movement, dropping, acting like she's holding the horn. Just make those movements a habit with whatever you're doing and it will stick..LOL Sound effects help..Sounds stupid, but it works. I even still end up making the sound effect when running, just habit..Kinda like a race car accelerating and then stopping..
I am Sparkly Meanie Doodie Head and I approve this message!