Line Driving Young Horses
As part of your groundwork, you may want to line-drive your young horse. This can be done with a surcingle; a bit is not necessary (halters, rope or web, are fine, as well as sidepulls).
You may want to be sure that your horse is very comfortable with you being behind him.
It's helpful for the first time or two, to have someone lead the horse, and then fade away after he understands the cues are coming from behind.
Driving thru the obstacles (serpentine).
Driving on the trails.
Please be sure to see the line-driving articles at Ground Driving and Neck-Line Driving