I have found the best and most effective tool (in my opinion) to quiet and level your hands while allowing the correct bend in the elbow. It then causes your body to be more quiet and life becomes so much easier. For real people.
This wonderful tool is your everyday, ordinary crop!
During our warm-up my trainer asked her assistant to grab me a crop. My stomach about fell through my stomach because last time I used a stick on the O she had done some pretty snazzy legwork that about left me in the dirt. She laughed at my face and quickly explained that I was going to ride around with it under both of my thumbs (across the tops of my hands) for the rest of my lesson. It was plenty awkward at first, and pretty sure I dropped the reins like 3 times, but as soon as I had my had coordinated it was so cool. It caused me to keep my hands at the same point a part, and off her neck. No more moving hands or stretching elbows.
So with my stead hands, bent elbows and a strong grip on the reins I was able to bring my body back and stay out of her way. O trotted and cantered around quietly, no head bobbing at the contact at all. It also clued me in to how lovely and sensitive she is about steering now. No more green horse rein cranking. I barely needed the reins to move her around, even over the fences. We did a neat little wiggly course to end the lesson. Jumps were small, we were focused on timing and keeping with the steady hand theme. She was bold and exactly what I needed, we ended on a neat little hop over the baby roll top.
She got loves and a nice walk-out since it was still cold (about 28 degrees), then all tucked into her blanket for the night.
Plus, good pony gets lots of treats!