Make it a habit to put your thumb on top of the steering wheel not wrapped around, if the front wheels hits something it won't break your thumb.

I would add to that, never steer one handed. I've got a loader on my N, and often am navigating my woods roads, which are full of rocks that just love to grab the steering wheel and try to wrench your arm off. Don't ask how I learned to always steer with both hands on the steering wheel, but at least it didn't involve any broken bones. Even without a loader on your tractor, hitting a stump or rock or hidden hole in the field just the wrong way can whip that steering wheel around so fast, it's unbelievable!
Carl