Photo 1. To bridge the reins, hold your outside rein (my left here) normally. Then lay your inside rein (my right) over the top of the outside rein. Hold your stick in your "bridge" hand.
Photo 2. I like to have my inside rein a touch shorter than my outside rein to help steer my horse, give him a slight natural bend and keep him from cutting corners. My outside rein comes out of my hand between my third and my little finger, but the inside rein goes all they way through my hand. That gives me a better grip and makes adjusting rein length while moving slightly easier.
Excerpted from "Beginning Adult Rider, Build Stronger Basics: Learn to Sit," which first appeared in the July 2003 issue of Practical Horseman magazine.