Here is the simple way to do this.
Start in your basic stance with your right heel off the floor and your left foot flat. Time his punch and drop your right foot flat, turn your weight over your right leg and get your left foot on the toe. This will lift your left shoulder and put your weight on the right foot and in position to throw a counter right.
This is FAR FAR from useless against a "right hook", or, a looping right hand. The more pronounced the loop in the punch, the more dramatically you put your weight onto the right foot. Works better against the loop, oops, "hook" that is prevalent today than it does against a true straight right hand.