For most people, the best way to teach a horse to understand an accept contact is by using side reins. Don't roast the girl over the fire for wanting to try this widely used and acceptable training practice.
Some quick tips for using side reins: Get the horse pointed in the right direction first. Put on the outside side rein and then the inside. Get behind the horse (not directly behind, just in a good position to drive the horse forward) and tell the horse to go. Some times if they fuss and drop a lot in the walk, it's better to trot them. Don't canter in them until the horse the horse is very balanced in that gait without them on. If you adjust them too loosely, it will just bump the horse in the mouth. You want the horse to be just about on the vertical (face perpendicular to the ground) while standing. When you change directions, take them off, turn the horse around and then put them back on.